Preparing For Power Failures

Many people simply take electricity for granted and make the assumption it will be there and people with disabilities are made false promises, that in the event of an electricity failure they may be provided with generators to restore their electricity for the duration of the power outage. Let’s look at this in a little more detail; first you will not be provided with a generator automatically as this is based upon need, and they have a finite number of generators as they simply hire them in and it depends on what their contractors have available at that time in single phase which is basically very few.

Generators are based upon need and those with life saving medical equipment are top the list and get their generators first, those with medical equipment which may save their life are next, and the disabled person with no need for life saving equipment is bottom of the list. Now look at the wording “you may get” which also means you may not get, but it is an additional incentive to convince disabled people to switch to a supplier, so basically little more than sales spiel.

Do you need to prepare for power outages? Actually yes it is better to be prepared so how do we go about it. In simple terms it comes down to what you have and what you need and if you have all the latest gadgets they will all require electricity and this includes your gas heating as it requires electricity to power the control circuits for the boiler to run. Without electricity you have no gas heating and it’s that simple. If you have an older house with a chimney and drain rods you can buy a chimney brush and get an old sheet to cover your hearth and put a small hole in it and push your rods through it and up your chimney to clean it, but this assumes a previous tenant hasn’t capped the chimney. You may get birds nesting in it during the summer and these nests and soot need removing to prevent a chimney fire as old soot exudes tar and this burns; instant chimney fire. You also need a source of fuel to burn, paper to light it, and sufficient fuel to burn for the duration of the power outage. You may be in a smokeless area and if you have a fire and others don’t you can be sure some idiot, usually a jealous idiot will report you and as wood smoke has a distinct smell it is easily detected.

What about your freezers? In reality most modern freezers will stay frozen for many hours if they remain shut and unopened and children are often the worst for just going into them for things and this lets the cold air out into your house you are trying to keep warm. With any freezer it’s as simple as keeping it shut and stopping people going into it and it will keep its contents frozen for hours.

Many people have many other things always plugged in and one maybe the television as it is switched to standby instead of switching it off, or maybe an electric clock which works 24/7/365 along with many other things in your home which you didn’t realised or forgot were permanently plugged in and drawing power.

In reality you need to go around your home and check every socket and appliance to see what is permanently plugged in and drawing small amounts of power and remember that a lot of small quantities of power draw soon adds up to a lot of power. While you are there you need to look at the manufacturers plates and check electricity consumption of any appliance you want or need power to in a power outage as this totalled up will give you minimum amount of power you will need.

Next is to understand things and a little maths is needed and knowledge of a simple formula as some items may be listed as amps current draw or wattage and we can work these out using our formula as we know the UK is 240 volts (other countries may vary) and this simple formula works for all voltages and currents;

VOLTS X AMPS = WATTS

WATTS ÷ VOLTS = AMPS

WATTS ÷ AMPS = VOLTS

With this formula you can work anything out irrespective of whether the manufacturer uses amps or watts to rate your machine/equipment. Many generators are rated in KVA and give two output ratings and it is crucial to understand this.

Our large energy saving American fridge freezer is rated at 240 volts at 2.5 amps and if we use our formula we get 240 V X 2.5 A = 600W. Now there’s a contradiction, American and energy saving in the same sentence.

If it is rated at 240V and 600W then we take 600W ÷ 240V = 2.5amps, so now it doesn’t matter which rating system the manufacturer uses as we can easily and quickly convert them.

We now need to go around and add up all the electrical appliances we may need in the event of a power outage and also those we don’t need which need unplugging so they don’t draw any power and you may not be aware of the huge numbers of people who don’t unplug things such as the Sky/Virgin boxes as one example or CCTV as another example.

Most people look to a generator as their first solution and finding the correct generator is crucial as they generally come with two ratings; first is the maximum or surge rating and most manufacturers use this rating as their advertised rating as it sounds more impressive. They have a second rating and this is their maximum continuous power output rating which is the maximum power they can continually put out and this is less than their advertised maximum power output.
If we take a fairly typical generator it is advertised as giving a maximum of 3400 watts out and is marketed as a 3400 watt output generator; but when we read the specifications it tells us that the continuous maximum power output is 2800 watts so why is this?

Most things electrical use more current upon start up and these are generally divided into “resistive” loads and “conductive” loads. If we imagine a traditional filament light bulb we know it works by applying a resistive load across a tungsten filament and it needs sufficient load to set it glowing and if it is rated at 100W it may need 150W for 5 seconds to get it working at full brightness and once at full brightness it only takes 100 watts to maintain this.

If our gas central heating system specifies a maximum of 800W this is what it requires and as it contains a circulation pump it needs to run the circulation pump by starting it up and getting the heated water circulating. If I take my heating pump it draws 720W while running, but on start-up it draws 1000W while the pump runs up to speed and gets the water circulating up to speed so it’s drawing 1000W for approximately 1-2 minutes while it does this.
Fortunately it’s only a back up system and runs on bottled gas and is only run up for testing and servicing twice a year as my main heating system is deep bore geothermal and requires no gas or electricity to run.

This is why generators have this surge capacity as the manufactures know electrical items draw more current or power while something starts up and gets up to temperature or full speed, and that this takes time to do this. Filament bulbs may take a few seconds and central heating circulation pumps may take minutes, hence a maximum power output and a maximum continuous power output. Maximum continuous power is sometimes called maximum rated power in certain advertising.

With our power requirement totalled up we can begin to look for a generator to run our essential requirements and if our loading totals 2950 watts then we need to look for a generator capable of giving over 2950 watts continually which is often termed its “rated power”. If we look at the above generator its rated or continual power output is only 2800 watts and isn’t sufficient for our power requirements despite being advertised as a 3400 watt unit and this means we need to go to a larger generator. In this manufacturers list the next size up is advertised as the 6500 watt unit and this gives a maximum power output of 6500 watts with a continual or rated power output of 6000 watts and this would fit the purpose we intend using it for with spare capacity. What does this actually mean? In reality it means we can run our basic requirements and have some spare capacity allowing us to use some lights or a small television and if it is auto load sensing it means that it will run at a lower engine speed to give our 2950 watts and save on fuel consumption.

Above we have quoted figures from a reputable brands petrol powered range. But is petrol power appropriate and this is a question which needs asking. In the UK we have recently introduced E10 petrol and this is causing numerous problems and this needs considering. Many cheaper generators will not run on E10 petrol and if it is a stand by generator you cannot store E10 petrol for longer than 3 weeks as the 10% ethanol content separates from the petrol meaning you have to have a nearby petrol station which is open when you need petrol. It also suffers from being “hygroscopic” which means the ethanol content absorbs water which also causes problems for the generator. Remember your fuel in the generator fuel tank has a vent and is exposed to air.

This raises the question of other options; many generators run on gas and many generator manufacturers offer a gas conversion kit for certain petrol generators and this is worth considering for a stand by generator as bottled gas can be stored for long periods and does not degrade after 3 weeks.

Diesel generators are often the best option as they use diesel and diesel can be stored in sealed containers for years with no degradation, so you can store its fuel in quantities for when you need it and just fill up from a sealed diesel container without hoping and praying the nearest 24 hour garage still has electricity to operate their pumps. Diesel generators are prohibitively more expensive than petrol generators but use much less fuel for a given output, they are generally more durable than the cheap mass produced petrol engines often made in China and they have much less to go wrong with them. Many diesel engined generators can run on different fuels such as 100% bio fuels and other transesterificated oils such as vegetable oils and you can often mix other products such as paraffin into the diesel up to a certain percentage and run it on this. You can also run a diesel generator on red diesel which is much cheaper and identical to white road diesel in every aspect apart from it contains a red dye and has a very low rate of taxation.

What should you look for? Load sensing is crucial as the engine lowers its engine speed to provide only the power required and while load sensing may be the preserve of large diesel engined generators, it is also fitted to many small diesel engined, and some higher end petrol engined generators. AVR or auto voltage regulation is critical for modern homes as this regulates the output voltage to prevent huge voltage spikes or surges which damage everything with electronics inside them and virtually every TV, kettle, toaster and most domestic appliances are electronically controlled. Obviously mobile phones, lap tops/tablets and home computers are electronic devices. In testing of non AVR generators we have seen voltages rise above 350 volts which would undoubtedly damage many items of household equipment.

Where should you site a stand by generator? Ideally it should be in a well ventilated building so it gets lots of clean air to run the engine, it should have the exhaust running through a wall to the outside to prevent any fumes or carbon monoxide entering the building. It should always be well secured and readily accessible with no flammable materials such as fuels, paints, cleaners, thinners, or spray cans near it as they are engines with hot exhausts. It should be as close to the house as possible and have a direct wiring to the house consumer unit using the correct size of cable for both current and distance.

How do you wire them in? in its most basic form the generator often has a control box and if it has the 240 standard plug sockets or both 240 and 110 volt sockets they are wired into this control box, you access this and connect your cable into the 240V side and run it to your house. Run the cable through your house to your consumer unit and secure it permanently in position, you need a plug and socket to connect it to your consumer unit and for most domestic generators I would recommend “commando plugs and sockets” which come in blue for 240 volts and in 16 or 32 amp sizes. Sockets have a flip top spring loaded cover which keeps fingers out and minimises the risk of electrocution and items such as dust and household dirt falling into it.

Your consumer unit has a double pole switch which is the wide looking block with two switches connected together and the mains power from your meter is fed into them, the live output side is connected to a live bus bar which is normally a coated brass strip. This runs to the far side of the consumer unit and the individual RCD’s connect to this by having a fixed clip on top which hooks on a plastic rail and on the bottom it has a metal slotted piece and you put an insulated electrical screwdriver into this slot and pull it down, you push the breaker over the live bus bar and remove your screwdriver. As you remove your screwdriver the spring loaded RCD has a tapered metal conductor at the back and the tapered section slides onto the bus bar and locks it into position and your house wiring goes into the top of the RCB to its designated circuit with screw fixings.

Other types have a copper bus bar running from the output side of the double pole breaker and this links all the breakers to it, they are all permanently live and the output current goes through the breaker and exits into cable terminations on the top where you connect your cables for individual circuits. The neutral goes to the neutral rail and all your neutral connections go into there, similarly, your earth connects to an earth rail and all your earth connections connect to it.
Identify your incoming power to your main double pole trip and this can be done by using a “test screwdriver” or an electrical multimeter, switch your main breaker switch off and the incoming side will still be live and your outgoing side will be dead. Identify the live and neutral on the dead side. Mount your socket in a suitable location and wire it into the dead side of your main incoming main breaker switch and connect your earth wire to the main earth and your socket is connected to your consumer unit.

Fit your plug to your incoming generator cable and ensure it has sufficient length to plug into its socket and it’s that simple.

Test by switching off your main incoming breaker and isolating your individual circuits by switching off all your breakers, go around your home and unplug everything so nothing in your home is switched on, plug your generator plug into its new socket and start your generator, you should now have power. Find your lighting circuit and switch its breaker on and go around your house and switch lights on and check they work, switch them off and switch the next light on and check it works; check all your lights one by one.
Isolate your lighting circuit by switching its breaker off and switch your sockets breaker on and go around your house with a small mains powered tool such as a small drill or lamp and plug it into each socket and switch your tool on to ensure all your sockets work. If you have a gas boiler you may need to reset it and relight it so do this and ensure it works, next plug in your fridge/freezer and check it works.

Why do you switch off mains power? Because if you don’t, in the event of a power cut you will be powering all your neighbours’ appliances and your generator will trip on overload, also you will electrocute any worker repairing the street mains.

This is the simplest and most basic set up and we need to follow certain procedures. In the event of a power outage you need a couple of handy torches you can instantly put your hands on in the dark and now you have some torchlight you begin your sequence.
Go around your home and unplug everything, and that means everything, switch off every light and lamp and remember items such as CCTV. Do not switch off the power breaker to your gas boiler if you have one.

Go to your consumer unit and switch off the main incoming isolator and all the RCD’s so everything is switched off, plug in your generator lead to its socket and go out to your generator and start it up, you should now have power to your consumer unit. Switch on the breaker for your gas boiler and your lighting circuit. Go to the room in which your boiler is located and ensure it is lit and running, you may have to reset it and light it and having the room light on helps tremendously; do not switch on any other lights. Leave your gas boiler running for a few minutes and switch off the light and switch off the lighting circuit breaker in your fuse box. You should now have the boiler heating your home so leave it for several minutes to let it heat your home again.

Go back to your consumer unit and switch on the breaker for your sockets, plug in your fridge/freezer and leave this for a few minutes while it runs and cools your produce, once it stops running you have both fridge and heating working.
You can then bring your lighting circuits back on line by switching the breaker on and confine everyone to one room and switch the light on in that room; children need watching because they develop a habit of going into a room and automatically switching a light on so watch for this. If you have any spare capacity then you can switch on more things and use this additional capacity, but avoid things such as plugging a kettle in and switching it on as the smaller items often consume 2Kw or 2000 watts and this will undoubtedly overload and trip a smaller generator.

Generators can cause other problems and this often means neighbour problems and the usual culprit is noise, if you have close neighbours and your generator is near your home then noise/sound insulation in the generator building is recommended and potentially vital.

If you have the money you can invest in a little box which connects to your consumer unit which measures the incoming power and if it fails it detects this and automatically starts your generator, the issue is cost and the units typically cost £1500 - £2000 and require an electrician to install it. You will then need a much better generator which has the auto start function and these are prohibitively more expensive, then you need the additional wiring to auto or remotely start your generator and for many people this cost is excessive and unnecessary.



If you don’t have the budget, room, or capabilities to buy and install a generator then it’s back to basics and the most basic item for light in a torch and simply buying a couple of torches isn’t the answer as this needs careful consideration to get it right for you.
Lighting has come a long way in recent years and simply buying a torch which fits in your pocket have long passed and LED torches and lanterns offer a lot of light from very small batteries, but many offer many gimmicks which you neither want or need in a power outage, so careful selection is crucial. Many people simply buy a battery torch running on traditional dry cells and buy new batteries and drop it in a convenient place and generally forget about it until they actually need it, or, they buy an all singing and dancing rechargeable torch and never recharge it and neither work when they are needed. Basic errors are common and occur all too often.

I would suggest a different option and this is a head torch as they provide a working light which means they light up a wide angle in front of you, but do not light up 500 metres away which is what you don’t want, they also allow your hands to be free. Many come with different light settings and a low setting may be ideal for walking around, but the higher settings allow work lighting and they have a long battery life and many work for over 8 hours on full or near full power.

This raises the common issue of battery run time which is common to all torches and while your all singing and dancing tactical torch with zoom and a rechargeable battery may last for 3 hours on a full charge, does it actually provide the light you need, and is your battery actually fully charged when your power goes off. If not it reduces the torches run time and while it may run for 3 hours on a full charge it may only work for 2 hours when you need it.

Lanterns offer the best form of lighting for a room and while many LED lanterns are rechargeable many are dry batteries and while their light output may be lower it is what is called omnidirectional light, or in simple terms it offers all round light instead of directional light. Some lanterns also come with a useful feature which is they are plugged in and left and if the mains power goes off the lantern automatically illuminates and gives you light instantly the mains power goes out and with fully charged batteries.

If you opt for traditional dry cell batteries for your lighting them try and standardise them to one size, typically AA batteries are the most popular and if you buy a new pack every 6 months you are assured power for your torches. If you opt for rechargeable torches then try to standardise them to a common plug such as the popular USB type C fitting as you can get a plug in charger to fit your domestic sockets which fits all your lighting and often they can be charged from a computer USB port, so options.

I would recommend two or three torches with long run times and the zoom able torches can zoom from a very wide beam to a long and piercing beam and you can zoom them out for a very wide beam which would supply sufficient light to a room to light in the event of a power outage.
I would follow this with several lanterns as they can be placed at strategic locations around your home and provide an all round light for that location and again the run time is critical.
If funds exist then a couple of plug in lanterns are always a good idea and if you site them in convenient locations they constantly charge and if the power fails they switch on automatically and are fully charged.
Forget those with gimmicks and this saves you money as you aren’t buying something you don’t need or will ever use and your money is better in your pocket to invest in more appropriate lighting.

Other lighting options exist and they are the wind up or kinetic torches, you don’t need anything for these and you simply wind them up for 1 minute and this charges the batteries or capacitors and these give many minutes of light from a 1 minute wind. These come as torches and lanterns and maybe worth looking at as supplementary torches as they need nothing other than winding.

Camping gas lighting is another option but are often more complex and these require mantles and these are delicate and often hard for some people to fit but they come in disposable gas container form and even petrol form and have the added advantage of providing heat as well as light. Some come with fuel bottles and these run on a variety of fuels ranging from petrol, diesel, aviation fuel, paraffin, and even liquid form gases.
Most popular are the gas lights which run on disposable containers and you either screw them on or push them onto the light, turn on the gas and push the igniter until they are lit, petrol lanterns require pumping up, opening the valve and hitting the ignitor until they light. Petrol units often state they can be run on unleaded petrol but in reality they run on a refined petrol which is available in smaller cans and this is more expensive but better as they don’t emit smoke and smells which they emit with unleaded petrol.

Perhaps my personal favourite is the Tilley Storm Force lantern as I have one over 80 years old and one which we were bought up with while camping, mine is the solid brass one and is still in perfect working order. These are more of a faff and use paraffin as the main fuel and they have a pre heater which is soaked in methylated spirits and once lit clamps on the main upright fuel rod once it is pumped up and lights the mantle and emits a large amount of light and heat, older ones are now collectable and you can get all the spares for them. These are lanterns you can read by and my mum used to do the washing in the tent and hang it up inside the tent once the Tilley lamp was lit and it dried in about 1 hour so they will easily light a room.

With lighting covered we now have to look at other things, what if your cooker is electric and you cannot obviously cook or make a drink. In reality the only cheap and viable option is to use portable cooking equipment such as that used in outdoors activities. Barbecues are the obvious choice as they are simply outdoor cookers and most people using them often have some charcoal left at the end of the season along with lighters or lighter fluid, so can cook. This is fine until you lose power in the middle of a bitterly cold winter when it is howling down with rain.

Gas cookers are the obvious choice as they are portable, can be used almost anywhere, and often provide a source of heat when being used in the house.
Basic single burner gas cookers are compact and portable and easily stored and can run from disposable gas containers which can often be bought cheaply at the end of the camping season and often in bulk packs which can be safely stored and instantly accessible. Some single burner cookers can be screwed directly onto the much larger Camping gaz bottles which have a much larger base for stability but require you to have the Camping gaz bottle, but their larger weight ensures their stability.
Larger gas cookers are available as double burner units and these require the larger gas bottle and regulator and have the added capability of allowing you to cook a meal using two pans instead of one and omit the limitations a single burner unit. Many models of double burner units now incorporate a grill and camp kitchens are readily available (at a price) which include a small oven to allow you to cook virtually anything you like.
What is the best option? For emergency use a single burner unit running from disposable bottles is the better option as its compact nature means it can be easily stored and it’s also the cheapest when you factor in a pack of disposable bottles as by prudent buying you can get the cooker and a pack of disposable gas bottles for under £25 at the time of writing. You can put a kettle on it to boil water for drinks or snack foods such as Pot Noodle or similar snack foods, cook cans of soup or even use a wok for more nutritious foods you may have in the house. In simple terms you can have a hot meal and drink.

Simple Projects 1

If you have some basic tools and rudimentary DIY skills and a little money which you can spend over time then you can ensure hours of bright lights in your home and the skills involve a little soldering and using basic electronic components and basic hand skills.

Car battery, ideally the larger the better as this gives more light output for longer and a leisure battery is the best option. Costs vary according to size and type of battery and manufacturer.
Digital multi stage battery charger which charges your battery and automatically switches from charging to a maintenance charge so you can leave it connected to your battery. Costs vary from £20-65 on Amazon.
LED lighting strip in daylight or bright white in a 5M length and self adhesive strip is a better option for many first time users and ensure it has cut points so you can cut it into pieces and the copper solder tags to solder your wires to, waterproof items are available but not worth the expense for our purposes. These come in various voltages and we need 12 volt versions. These vary from around £10 – 18 on Amazon and forget those with dimmers or other electronically controlled functions.
Voltage regulators often called “buck convertors” are a DC to DC voltage converter and they are often called either 7812 or 7912 regulators and the first two numbers state what series they are and the final 2 numbers denote their output voltage. Therefore a 7812 is a 78 series regulator with a regulated output of 12 volts and a 7912 is a 79 series regulator with a 12 volt output and either will do buy the 79 series regulators control the output voltage more accurately than the 78 series, but either will suffice. Packs of 10 X 7812 regulators are available for around £4.99 on Amazon
Voltage converters come in something called “packages” and these denote the pin layouts and for our purposes we need to check and select the TO 220 package and they all have an amp rating and for out purposes I would suggest the 3- 5 amp rated unit.
Heat shrink tubing and I would suggest either 3 or 4mm diameter as this shrinks to half its diameter when heated.
Aluminium extrusions, these are optional and many use them to stick their LED strip to but most people can make their own from sheet aluminium.
Thermal transfer grease as this is used on the rear of the voltage regulator which has a metal section and this grease is applied to it to conduct the heat from the regulator to the metal plate it is mounted on to keep it cool and within its operating temperature range.

We can assume that you have epoxy glue, small nuts and bolts, soldering iron and electrical solder and a cordless drill with small drill bits, if not it is worth getting them along with some short nuts and bolts and possibly wingnuts.

Now we need to look in more detail and first we need to understand batteries and this begins with their ratings, many are rated in an amp hour A/H rating which is their theoretical output rating, and their cold cranking amp CCA which is the power they give to crank your engine and we can disregard the CCA rating.
Batteries are rated on something called the 20 hour cycle rating and if we assume we have a battery with a rating of 100 amps rating it theoretically provides 100 amps for one hour and in reality if you drew 100 amps it would only last for minutes if you were lucky. To establish its accurate output we use our 20 hour rating and we divide our battery rating by 20 so our calculation now becomes 100 amps battery rating ÷ 20 hours: so 100 ÷ 20 = 5 which means that if we draw 5 or less amps from our battery it will provide this for 20 hours. If our battery is rated at 80 amps the calculation is the same, it becomes 80 amps ÷ 20 hours or 80 ÷ 20 = 4, so as long as we draw 4 or less amps it will last for 20 hours. What type of battery? While a car battery will suffice you can opt for a leisure battery as these are a heavier construction and will stand more abuse on the charge/discharge cycles and a better option if funds permit, most batteries come with tapered round posts or flat posts with a hole, the flat posts are the better option.

Now we look at our LED strip and specifically its ratings and many come with a rating of 24 watts per 5M length and if we do our calculations 24 watts equals 2 amps for our 5M length or 4.8 watts per metre. You need to look if it can be cut and many can every 4” and if they have the cut line clearly marked, and if they have the two copper dots either side of the cut line and if they are clearly marked + and – so we can identify our solder connections. Remember that all LED’s are polarity sensitive and equally all LED strip is polarity sensitive.

Before we begin building we need to site our battery and charger and while most people may site theirs in a workshop, garage or shed, some people cannot and your battery needs to be accessible and easily carried into your home when the power goes out. Similarly it needs siting inside your home and it needs to be accessible but out of the way and if you have a house it needs siting to run lights upstairs as well as downstairs; similarly a bungalow or flat on one level may need it siting centrally and all the cabling out of the way so you don’t trip or fall over it in the dark.

Let’s begin building; firstly we need our cable runs establishing and we need sufficient cable for this and we need small plugs and sockets so we can connect them together and light up our areas, then we need to establish which areas we need lighting and establish how we are going to run our cables. For upstairs lighting the bannister is the ideal cable run as these can be placed on the bannister stands or the bent metal at the back which holds the rail and we can use items such as Blu tack to hold the cable in position. We can mount our lighting so it shines over the landing and possibly into the toilet and bedrooms as not much light is needed for these areas. Many houses have pictures on the wall downstairs and these are ideal for draping cables over and they are up and out of the way, you can use items such as masking or sellotape to temporarily hold your cables onto door frames or existing light fittings.

We begin with the battery itself and many provide 12.6 volts for a fully charged battery and we need to provide our LED strip with 12 volts and we also need to potentially provide our regulator with a heat sink to cool it and while aluminium is ideal we use this. We take our chosen battery and look at it and measure between the battery posts or terminals and either cut, or form an angle iron to fit our battery and as every car or leisure battery has a flange and the space above it is where we ultimately glue our angle iron with the return over our battery. Ensure it does not cover any plugs or access points to fill the battery if it has them.

Put the angle iron into position and clamp it, put the voltage regulator into the angle iron at the positive terminal end and locate it, mark the hole to mount it and drill through the angle iron and bolt it to the angle iron with the metal side flat to the angle iron. This bolthole is the top, it must have the bulge and lettering facing upwards and the three pins are the bottom, if we look at the bottom pins we need the left hand pin and strip a bit of our wire and tin it and solder it to the very left hand terminal. Now we cut it to length and place a piece of shrink wrap over the wire and slide it all the way to the regulator terminal and over the soldered joint and the terminal itself and apply a little heat from our soldering iron and watch the tubing shrink. Now we strip a little of the insulation and crimp a ring or fork terminal to this end and solder it on for additional strength and a good contact, do not connect it to the battery positive terminal +yet.

Next we crimp a ring or fork connector to the end of our cable and this connects to the negative terminal of our battery and cut this cable to length and strip a little of the insulation for soldering to our regulator, we cut a second length of cable the same length as this runs to our plug. Tin both ends after twisting them together and fit a piece of heat shrink tuning over this end and slide it down the cables and solder these two cables to the centre terminal of the regulator and slide the heat shrink tubing back over the soldered ends and regulator terminal and shrink. We now have power in and earth to our regulator and the earth lead from our regulator to our plug, select your chosen socket and crimp or crimp and solder this to the negative side of your selected socket.

Now we turn our attention to the power out from our regulator and this is the remaining right hand side pin and if we cut our cable to suit we simply strip a little of the insulation from it and tin it and solder it to our socket and our power regulation unit is complete. If you want two or more circuits then simply add regulators and sockets to your heat shrink strip for the appropriate number of circuits you need. Unbolt the regulator just enough so you can apply the thermal or heat transfer grease under it and retighten the mounting bolt and the regulator heat transfers to the aluminium and cools the regulator.
With this completed you bond it to the side of the moulded flange by roughing up this area of the battery and aluminium strip, clean them both and apply epoxy glue and clamp it in position for 24 hours or whatever time the manufacturer recommends to cure. You now have your completed power source with regulated output and you can put this into its final position in your shed, workshop, or garage and fit your charger and bet it charge up fully.

Making the lights is actually very simple and you have a whole range of options or styles to choose from and you can make them to light an individual area or make them to light two areas by making your light and installing your LED strip to both sides if you like, or simply one side, it’s your choice.
In this section we will assume an average house and you want a doorway light which lights up a room on one side and a passageway on the other side with enough light to adequate light to see.
Lights will be wired in series and basically it means that we will wire the battery to our first light, our first light to our second light, and our second light to our third light downstairs; we will then wire in parallel for our upstairs lights and then run them in series. This is the reason we need to know the exact location of our lights and minimise the amount of cable we use and ultimately buy and the ideal location for our temporary cable runs when we use our lighting.

We begin with our nearest downstairs light to the battery and site our intended cable runs from the battery to our first light. If this is fitted inside a doorway with a wooden frame I would suggest using sticky backed Velcro and aluminium angle iron, in reality you can use anything but remember LED’s run hot and aluminium conducts heat away and heat conducted away equals reliability.
We look at the cut lines on our LED strip and if they are the fairly standard 4” centres we work to 4” lengths; if we are lighting a living area which comes off a passage the living room needs more light and the passage less light so we cut our aluminium to 26” long and fit this to the door frame. We do this by cutting a little piece of our Velcro into 2” strips and we need 3 of them, stick them to our aluminium and the corresponding pieces to the top of the wooden door frame so we can mount the aluminium easily and remove it and leave the Velcro strips on top of our door frame. Next we need to look at our light requirements, the side shining into the living area needs more light than the side shining into the passage so we cut 24” of lighting strip at the cut line and stick it to the side pointing into the room and 12” of strip for the side pointing into the passage and we stick them onto our aluminium angle iron.
We find the location of our solder tabs on the end nearest end to our battery and note which is + and which is – and solder our wires to them, we now run our two cables back to our battery and connect the plug noting the polarity and ensuring this is correct and if we plug them into our battery sockets this section of strip should illuminate on the wired side. Unplug this from the battery and run two cables from the opposite end of the strip which are obviously soldered to the strip, back across the top of our aluminium and solder them to the strip on the other side and check to see if they are working by plugging into the battery.
You hold these cables in position temporarily using tape and mix a little epoxy and put a few mixed drops over the cables and onto the aluminium and let it set, and the cables are held in position.

On the only unsoldered end of your cable strips you cut two short pieces of cable and solder them to the solder tabs and connect to your socket for your next light.

Some useful tips are to thoroughly clean your aluminium strips prior to working and to let this thoroughly dry, follow any manufactures instructions regarding the mounting of the lighting strip. In many cases the adhesive strip is poor and will become detached when the LED’s are illuminated
as the heat softens it. In such circumstances we lift either end of the LED strip and apply a little epoxy under either end and hold them down until it cores then apply a little more over the top where the solder terminals are located to it insulates them.


Simple Projects 2

In project 1 we bought a standard 5m strip and if we build our lights as above it will give us 5 lights and as 5M = 16’ this means we have 1’ or 3 X 4” pieces left and we can use these, we have already bought them, so let’s put them to good use.
Many places supply good 4A/H batteries and these range from alarm back up to mobility scooters and these batteries are available cheaply and often locally and they have flat sides as they stand on their base and many can be used in any orientation. We have bought a pack of voltage regulators and undoubtedly have some wire and thermal grease left and as we keep epoxy glue in our homes we can simply buy a battery and use what we have already got.
We cut a piece of aluminium plate to 6” (150mm) long and 2” (50mm) wide and bend the edges (about 3 mm) up at 90° to give us a small channel and mount our 4” strip right at the top, we mount our voltage regulator at the bottom underneath our LED strip and wire this to our light strip as in project 1 but include a switch between the battery + and the voltage regulator.

This now gives us a switchable portable light which can be located where you need it and assuming the above figures it is only consuming 1.6 watts and using a battery with a capacity of 48 watts and this should give us around 30 hours of lighting with a full charge. Maybe you have an awkwardly laid out home where you cannot readily run your temporary wires to safely and these small and portable lights would give you some illumination to light them up if the power goes off, they also make useful work torches/lights for many tasks around the home. If you have three strips of LED lighting strip left you can ultimately buy three 4A/H batteries and have three lights.

Your posts are legendary Assassin, really. What will the younger generation do when there are no more (real) men around any more who will be (some already are) totally or mostly impractical.

They will have to learn the skills and YT just doesn't cut it, they are dumbing down everyone and this includes skills and abilities. Traditional apprenticeships and Degrees have gone the way of the dodo and they have simplified them to the point of stupidity so everyone can have a Degree on their C.V. which seems to be the norm for the most basic level of jobs.
Indeed, how many could or would have to study for an apprenticeship and Degree in parallel and spend 14 hour days studying, they would be lucky to do 8 hours then give up citing stress or mental health or whatever the current vernacular is and achieve nothing.

I didn't believe you could get a Degree in making cheese on toast or Coronation Street until SWMBO downloaded a local college, now changed to a university had them listed on their curriculum.

Sadly I agree.

I have bought 2 petrol generators, do you think I should swap them for diesel so they could run off cooking oil? I guess the petrol ones won't run off cooking oil and I didn't realise that you can't store petrol for very long so not much point trying to stock up on petrol for the generators

yes diesel much better for several reasons including the use by date on petrol.
you can run them on waste cooking oil which has been processed, you can also pyrolyse plastic waste and obtain a usable diesel fuel.

Thank you, I have just looked at pyrolising plastic but all I can find is the huge plants used for it. Is there a simple DIY way of doing this?

Also I stored a Jerry can of petrol for my generators a couple of weeks ago, how long can I keep it or should I just use it now rather than waste it storing it? Sorry to keep bothering you but you seem very knowledgeable and kind enough to reply

it depends on the type and brand, you should be able to get the info online but 6 months is general.
pyrolysis of plastic is still pretty unherd of so you would need to become your own expert and build a small reactor , i was just saying its possible.

Ok Thank you, my son is an aircraft engineer so may know something about it(hopefully) do you mean 6 months for the petrol storage?

yep!

Thank you so much for your help.
I work as a support worker dealing with debts, housing issues and benefits so if you or anyone else needs help with these things I am happy to help if I can

Fiona wrote:I have bought 2 petrol generators, do you think I should swap them for diesel so they could run off cooking oil? I guess the petrol ones won't run off cooking oil and I didn't realise that you can't store petrol for very long so not much point trying to stock up on petrol for the generators

Not necessarily as they are going to phase out red diesel so the low tax exemption fails to exist and the onl;y diesel will be white diesel or road diesel which is heavily taxed and I wiuls look at the options before proceeding and see what suits you best and obviously your pocket.

Instead of having to buy super unleaded petrol at top prices and storing it for a season in sealed containers or normal E10 which absorbs water and goes off after about 3 weeks you switch to gas, many generators can have their inlets changed to run off gas and this maybe a better option as you only have to convert them using the gas conversion kit and have the gas bottles to run them off and this may have financial implications, most gas suppliers charge either an annual rental or a one off deposit on your first bottle and once this is paid you either have the bottle for a year for annual rental or the bottle for life if it is the one off deposit and in either case you swap your empty bottle for a full bottle and only pay for the gas.

Therefore, you need to find out if your generator can run off gas, can it be converted, and how much does it cost, and how much will the gas cost.

Pyrolysis of plastic requires heating stages and they run several stages and you need to know the temperatures of these stages to get effetive fuel, it is an extremely labour intensive and long winded process and one which requires a lot of wood for the heating stages.

Putting a 12 volt circuit into your home isn’t as daunting as many people think and as part of the prepping series I thought I had better explain this so others can install such a lighting circuit in their homes so they can run basic home lighting in the event of a power cut.

We begin with our supply and currently a large lead acid battery is the best power source as they are durable and stand a lot of abuse without complaint and they have proven themselves reliable over several years, and I would suggest the better option would be a leisure battery of around 110/115 amps capacity. These are currently the most popular size for motorhomes and caravans and leisure batteries have a better and more substantial construction to withstand heavy abuse over standard car batteries and a 110 amp battery provided gives us 1320 watts of power and a working current of 5.5 amps for 20 hours based upon the 20 hour cycle.

If we look back at previous articles we have all our calculations and how to do them and we also found that LED lighting strip came in 5M or 16’ lengths and they had cutting points every 4” and they drew 2 amps of current per 5 M length and they gave 48 X 4” pieces if they were cut into 4” lengths at their cut points. This equated to 4.8 watts of current draw per metre if we wanted our other equation and this gives our starting point for our circuit.
Knowing our lighting strip draws 24 watts or 2 amps at 12 volts is our starting point and that it has cutting points every 4” gives us potentially 48 X 4” pieces from our 5 Metre roll and we can leave several pieces attached as long as they are 4” multiples such as 8” or 12” lengths and each 4” piece consumes 0.5 watts per 4” length. Therefore an 8” piece would consume 1 watt and a 12” piece would consume 1.5 watts as this is 3 X 4” pieces.

Next we begin the most important and critical stage and this is the planning stages as this cannot be ignored or short cuts taken if we want a true 12 volt wiring circuit in our homes and that our requirements are met for safety, convenience, and usability if we suffer a power cut. You can also make any upgrades at this stage and incorporate them into your designs as a small 12V fan may be plugged in during the summer months and they consume 5 amps so our circuits are upgraded to carry this amount of current.
We may choose not to use LED strip and build our lights from an LED cob chip for each room or use LED bulbs of 12 volts as used in cars and again we need to add up our total power consumption for all these items and stick below the 5.5amps or 66 watts draw from our battery and maintain its full capacity of 110 amps for 20 hours.

We begin our home survey by establishing the number of rooms we have and how many of them need lighting and how much light they need and how and where we are going to position our lights and for these purposes we will assume we have elected to go with our LED strip to make our lights. Obviously a kitchen and living area needs more lighting than a toilet or passage so we can allocate our lighting strips to these rooms, and this is what we need to consider, our priority areas.
Do we have a house or a bungalow? Because with any electrical circuits we adopt best practice and run these above the rooms and do drops down and for a house we heed to access the void between the upstairs floor and downstairs ceiling to run out cabling and then up to the loft through the cavity in the wall. For a bungalow it is simpler because we need to simply access the loft.

Now we need to site the battery and ensure we can charge it and I would suggest a multi mode smart charger which can charge, drop to a maintenance charge, and have a low temperature setting as batteries charge differently in low or freezing temperatures and having this capability ensures that your battery is always fully charged and ready for use. Therefore we need a covered position close to the house which has mains electricity to power our charger to charge and maintain our charger and be sufficiently well ventilated to prevent up a gas build up during charging and discharging and be sufficiently well protected from frost and freezing temperatures. I would suggest NOT having your battery in your house unless it is totally necessary as ventilating it means cold air in a house you are trying to heat and keep warm.

Now we need to look at the practicalities and realise our normal living area may change and if we have a log burner in one room other than our normal main living room it makes sense to use this room as our main living area during a power cut as it has heat and the potential to cook so lighting seems to be a no brainer.

If you don’t have a log burner and a sufficiently sized kitchen it would appear to be the best option to use this as the living area if it has a gas cooker which is being used to cook and giving off heat and these are the types of thoughts and adjustments you should be thinking of. What else would I need 12 volts for should be another question and a simple answer would be to charge a mobile phone or laptop should it become necessary and this may influence your type of charging facility and normally a car cigarette lighter would be used so why not use one. Many are rated at 10 amps so it makes sense to uprate your wiring to that above the full capacity of your total potential load and if your phone charger uses another 2 amps you need wiring of at least 10+ 2+ 2 amps so you can run your telephone and laptop charger as well as all your lighting and the next standard size cable rating above this is twin core cable rated at 17 amps so this choice is already made.

Let us look at a typical house and everyone will have to adapt this to their own home; we assume a standard three bedroom house and we can work our lighting out.

Living room containing our log burner, 2 X three strips or 12” strips for our lighting or 6 pieces.
Kitchen where we prepare and cook our food 2 X three strips or 12” strips for our lighting 6 pieces.
Downstairs passage from the front door 1 strip to provide token lighting to pass through.
Downstairs toilet 1 strip to provide enough light to see the toilet and toilet paper and wash your hands.
Porch light to see the front door 1 strip which is switchable.
Other downstairs room which is not normally used or was your main living room 1 strip for security.

If we can cut our 5M strip every 4” and give ourselves 48 pieces of LED lighting strip we can see that just to light downstairs we have only used 16 pieces of it and this is only one third of our strip so I would always suggest using a strip over our battery so we can see it.

Stairs two single strips to light the entire staircase as people have a tendency to fall on them in the dark and by lighting both the top and bottom you have them all covered.

Upstairs bathroom/toilet 1 strip to provide sufficient light.
3 bedrooms means a single strip each as you don’t really need light to get undressed and into bed so three strips.
Top landing 1 strip and sometimes it may need two lights depending upon size and layout.

Even now we have only used 25 of our possible 48 pieces of LED strip which is just over half and if necessary we can double up on some strips to give more light to an area or we can light up other rooms such as a larder/pantry or even a conservatory as these maybe places we choose to exit and enter our home. This is useful as you can close a conservatory to house door and open a conservatory to outside door to minimise your heat losses which is beneficial if you have a log burner and it is lit to heat your home.

Now a note on security which was touched on; in the event of a major power cut in an area where every home and business has a power outage the thieves emerge and this is for several reasons:

They like the dark and this means cover for them and can go out thieving and will if they know the power will be if for a long period.
If homes and businesses have no power they will have less security and unless they have back up systems most businesses and homes will lose CCTV and their alarm batteries only have a short life of around 2-3 hours before they fail.
Any businesses with security lighting on PIR sensors will not work and they can steal anything in total darkness and not be seen or recorded and diesel fuel is apparently a prime target for thieves.

Therefore it comes down to a simple thing; you have lighting and they know that most people don’t have lighting so you must be in and if you shut your curtains and they can see a room is lit up and they cannot hear a generator they will assume or work out you have a back up system and this would likely be a power bank. If this is a power bank then your lighting is on and you have mains power and your CCTV system must be working and recording them so they tend to avoid your home and not even walk past in case your security cameras catch them doing so and basically they go elsewhere where there is now no security. Why risk getting caught robbing someone for £20 worth of goods when you can rob an unsecured business for £thousands for the same risk. If they hear a generator running it becomes a different matter as this may be worth pinching and you can suddenly make yourself a target for certain types of criminals.

Running our cables is next and to determine the route we need to make our next decision which is which rooms get 12v power and lighting and which don’t and how are we going to deal with this power to power our lights on our chosen rooms. I would suggest using a standard electrical pattress (back box) of 30mm depth and fitting them with a blank front and drilling the top with a hole large enough to fit a rubber grommet and pass your cabling through this to stop it chafing and attach a small connector plug from an automotive supplier as they are cheap and can handle 30 amps. I use something called Mini connectors as these can only fit together one way so you cannot get anything connected the wrong way round and get reverse polarity on LED lighting. These connectors work by getting the male and female plastic housings separately and the male and female connector pins in a bag which can be crimped and soldered to the 12v ring main wires and if they are crimped and then soldered with electrical solder you have a certain electrical connection.
I use 17 amp rated twin core cable as it comes in red and black and has stranded cores which can be fed into my pattress and cut, both red ends are twisted together and soldered and crimped onto my terminal followed up by soldering the crimp. And this is repeated with the black wires. I like to mount pattresses near to the ceiling to keep the wiring runs as short as possible as I can reach them but people must make their own decisions where to mount them; I also ensure several screwdrivers are around the house so in the event of any power failure a torch or head torch can be grabbed and the blank pattress front can be unscrewed one side and slackened off on the other side and the front rotated and locked open.
I prefer to make any lighting with catches or spring clamps so the cable can be plugged into the socket in the pattress and the light clipped to it and being high up means it, and its wiring is out of the way and unlikely to be hit or caught by anything. Basically it is a neat and fairly compact installation.

Once all the cabling is run through all the ground floor connections it can be run into the house cavity and into the loft for the upstairs rooms.

There are variations to this and where some lights may needs switching and I prefer the rectangular automotive switches as a slot can be cut into the side of the pattress and the switch inserted and for a light such as porch or toilet lights, they can be switched off when not in use to save battery power. Much the same thing may happen in a bedroom where the light may be on for a short while and then switched off and possibly switched on in the night, or for stairs lights which may only need switching on for people to go upstairs.

If a phone charger is installed this is better switched as these can draw large amounts of 12v power and I would only suggest charging one phone if it is getting low and keeping it for emergencies such as 999 or 101 calls or checking on elderly or disabled family members. Remember that in a power outage any modern home phone is plugged into the mains via a transformer and if the mains is off then their home phone won’t work either and I would suggest getting any such people to switch their mobile phones on in the event of a power cut.

I would suggest having your light on at your battery because you can see it and if this light goes out it is a good clue to either your battery failing or a poor connection at your battery which is clearly visible by having, or not having your light on.

In reality you will have around 55 hours of light with a fully charged battery with all your lighting strip being constantly used and if your house is illuminated with our suggested 25 strips this would be slightly over 1 amp and the battery should last for over 100 hours. If we equate this to winter lighting then using it from 6.30am until 8.30am means 2 hours use in the morning and if it is used again from 4.30pm to 11.30pm it is 7 hours so a daily use of 9 hours and the battery should last the whole week without being charged to give us lighting.

How do we connect to our battery storage facility? Actually you can get 20mm semi rigid and flexible cable conduit along with an array of corners and angles as well as wall mounting clips and anyone with basic DIY skills can install their own 12 volt DC lighting circuit in their home.

Home built generators shouldn’t be overlooked by the keen DIY’er as they can be simply constructed using basic car components and following a few basic rules generated by a little understanding of the process and how we achieve the best results from our little project.
Petrol generators in a practical size are on sale for a little over £300 but they are of poor quality and while many offer 12volt battery charging; my testing has shown that many cheaper or generic generators 12 volt unregulated outputs would certainly damage a battery and not charge it.
Petrol has issues and storage issues are common with the E10 petrol and those are that petrol and ethanol separate out and that the ethanol content is hygroscopic or for those less technical it means it absorbs water and as everyone knows water and petrol don’t mix. This has other implications and these are that E10 petrol has a very short storage life which is around 3 weeks unless it is constantly agitated and you cannot store large quantities at home so when you come to use it you may find it has a layer of water with a layer of ethanol on top with a layer of petrol on top of that.
This causes technical problems and these are directly from the separation of the components of E10 petrol and the first is rust caused by the water element in contact with steel components, then the neater ethanol component corrodes and eats aluminium and their alloys and finally this is sealed in by the petrol.
This causes other issues as any generator needs to start and run on demand and if the petrol components separate out the generator will be picking up pure water and will not start, then it will pick up pure ethanol and any contact with aluminium will start the digestion and erosion of these components; and all leave you with a new generator which will not start and run when you need it.

For the basis of this project I will be using a Petter diesel engine which is many decades old and is rated at 4.5HP @ 1500 RPM and came from a diesel cement mixer, for the alternator we will be using the popular Bosch K1 12V alternator as these were found on many German and other countries cars and ranged in output from 40-180 amps.
I chose this engine because I have an affinity for them because as a child I worked on them with my father who worked for Petter and was based out of their Wymeswold division and I went around the area working on them with him. My other reason is that they are as simple as sin and simple means reliable and they run off any diesel and are free of the petrol engine problems and as long as they have diesel and air they run and they come as variable speed or fixed speed units and mine is configured as a fixed speed unit.
Their main benefit is their simplicity and economy and they can be hand started from the crankshaft or camshaft and you can take power from each of them to power equipment and they are very fuel efficient and at the 1500 RPM setting they would run for a 10 hour work day on less than a gallon of red diesel. At the 1800 RPM setting they would consume around a gallon of diesel for the same 10 hour day and these single cylinder engines were fitted with a 1.5 gallon tank which could be sealed from the atmosphere if the optional filler cap was fitted. To start them you moved the spring loaded throttle to the run position and the end dropped and this was the speed setting, you fitted your starting handle to either the crankshaft or camshaft, lifted the decompression lever and turned it until you were turning it fast enough and knocked the decompression lever down and off it went. They started and ran at sub-zero temperatures of -30°C to desert heat and never failed to start and this is why so many were fitted to considerable amounts of British plant and equipment; and the reason there are so many good ones still running well after their 50th birthday. As many are now deemed obsolete because they never met any emissions or noise standards they were replaced by many newer engines such as Lombardini, Hatz, Steyr, Kubota and Yanmar to name a few they are available secondhand at reasonable prices so may be worth looking at. These engines have many nice features and these may be nice but in the event of a power cut they don’t start and this can be an issue as more complex means more to go wrong and it often does and always at the wrong time, when you need it running to provide power.

Bosch K1 alternators were well regarded as reliable automotive alternators and were fitted to many vehicles and plant and were not only reasonable sized but could stand a lot of abuse and were made in both 12v. 24v and 48v versions in a range of outputs for Lorries, cars, and plant and heavy equipment.
We need to know a few things and we begin with the minimum and maximum speeds and these are the alternator shaft speeds and they have a minimum speed and a maximum speed and the maximum speed is what we need to know and this is a shaft speed of 8000 RPM as the nearer we can get to this without exceeding it, the more power we will get.
All alternators need exciting and unlike your girlfriend or wife a bunch of flowers and posh chocolates won’t do it and on the rear of the alternator we have two connections; a large bolt on connection for the main power out and a smaller excitation wire which is an earth while the alternator is stationary. Therefore we need a small voltage to excite the alternator once it is turning to make it produce power and to do this we run a 12V power supply to a power switch and then through a bulb so the filament acts as a resistor and then runs to this excitation terminal.

We now know the important information and that is the engine crankshaft speed for this engine is 1500RPM and the camshaft speed is half that of the engine speed and that would be 750 RPM and the maximum shaft speed of our alternator is 8000 RPM so now its maths time. The nearer you can get to 8000 RPM shaft speed the better as this gives the highest output and we know we had a pulley of 50mm diameter for a Poly Vee belt for our alternator and that if we multiply out crankshaft speed by 5 it gives us 7500 RPM and that is close to out 8000 RPM without exceeding it. If our alternator Poly Vee pulley is 50mm diameter and we multiply this by 5 it gives us 250mm or a Poly Vee pulley diameter of 250mm for our engines crankshaft and while one was available I had to machine a boss for the crankshaft to mount it to.
Next I checked the rotation of both the engine as they also come in a reverse rotation and this one wasn’t configured for reverse rotation and it was time to make a base which I fabricated out of old 4 X 2” steel channel which I recycled and this had a steel plate of ½” thickness welded between then to space them apart and drilled to mount the engine. Alternator mountings were fabricated with adjustment for the alternator to tighten the belt and an appropriate sized belt was fitted and I modified a spring loaded belt tensioner from a Fiat JTD engine to keep the belt appropriately tensioned.
With everything fitted to the new frame and the alignment checked it was time to remove the drive belt and run the engine and check the crankshaft speed with a tachometer and this was 1520 RPM which was an appropriate crankshaft speed for out purposes and the battery box was fitted to the frame to hold our battery. I used a 100 amp rated battery with flat terminals and fitted this into the box and made a cable up rated at 175 amps and fitted this to the alternator and battery and made an earth cable from the battery to the steel frame.
Now it came to the technical bit of exciting the alternator and this was done by using a switch and a small indicator light as found on many cars and this had a small 3 watt bulb fitted which acts as the resistor and this was fitted as indicated. First I drilled a hole for the indicator light and mine was red, then a slot was cut to house the switch and this was inserted and the wiring began and I used 8 amp rated wiring and crimped and soldered a ring terminal to the battery end of the wire to fit onto the battery + terminal. This ran to one of the switch connectors which were standard 6.3mm male blade connectors so a female was crimped and soldered on and pushed onto the switch, another short cable was made up with twin spade connectors which ran from the other pole of the switch and to one of the indicator light connectors. Our final cable was also a double push fit female connectors which went onto the other light pole and to the excitation terminal of the alternator and our circuit was complete and we had an engine with 120 amp output alternator running at 7600 RPM and it was tested.

With our meter connected I switched the ignition/excitation switch on and the light was red and when I hand started the engine it began charging and the warning light went out and it became self exciting and the clamp meter showed an output of 107 amps. My final job was to connect an Anderson Connector rated at 200 amps so I could connect other high power items to our 100 amp car battery and either run or charge them and I fully intended using this to power a battery pack and charge it and this will be the basis of our next article.

Building your own battery pack is simplicity itself and while there are things you need to understand these are minimal and easily understood by almost anyone and the first involves charging as a fixed rate or smaller of 4 amps will charge a battery slowly but it will eventually charge it. If you charge the same battery with a much larger 10 amp battery charger it will charge it much quicker and if you have a digital charger rated at 10 amps it should charge it even quicker.

Building a battery pack is all relevant and our first rule is to get the best batteries you can afford in the largest size you can afford to suit your needs and for the benefit of this project I used 3 X 280 A/H (amp/hour) batteries which were wired in parallel which means they were wired positive to positive to positive and a tail was left. The negative terminals were wired in the same way, negative to negative to negative and a tail was left and wiring in this was gave us our 12 volt output but with three 280 amp batteries gave us 840 amps or 10.080 watts or 10Kw of power.
Intentions raised in the design were to use the aforementioned engine to charge the battery pack and an Anderson connector was fitted to the tails so it could be plugged into our Petter engine project to charge these batteries and they were going to be wired to a 1500W invertor. This was to run a large freezer full of food which meant it wasn’t running continuously and it consumed 900 watts during its running period which was timed at 3 minutes of run time per hour at the lowest or coldest freezer setting and as long as the door remained shut it would stay frozen for 12 hours or more.
This battery pack was going to be on wheels so it could be moved to our generator to be fully charged and wheeled back into the house where it could be plugged directly into the freezer and left and it was established that it would run for around 4 days before it needed recharging.
Next we got the invertor instructions and specifications and noted it had a minimum battery size of 120 amps and at 640 amps we were well over that and even at that current it wouldn’t be too much input for our invertor and damage it.
The carriage was made from 50 X 50mm angle iron so the batteries sat inside and on either side was a plate welded to form two sides and uprights and on top of this was a thick aluminium plate on which his 1500W inverter sat and the aluminium plate acted as a heatsink. This was fitted with a handle at the front and two industrial castors from supermarket trolleys with two fixed wheels at the rear and as his engine was mounted in his shed he could simply plug it in to charge it before pulling it back to his house to plug his freezer/s in and run them.

He bought a decent quality inverter and not a cheap one and he is now integrated so he can be fully off grid and his inverter system is an integral part of this and his had low voltage shutdown, overheat warnings as well as overload protection.

His (mine) old Petter engine was modified as they originally came with a basic pepper pot silencer which basically didn’t silence them and I modified it to take a much better home made silencer and it is very quiet now and has a stainless steel exhaust made from 40mm T304 tube. This runs from the engine and into his new silencer and out through his outhouse wall so exhaust gases don’t build up inside and suffocate him and they have a flexible joint to allow for some vibration of flex and he has two X 45 gallon drums of red diesel with fuel conditioner added. Being fixed means he can use it to power up his power bank which is used to run his freezer. This takes around 20-25 minutes to fully charge and he has a lighting pack to power his emergency 12 volt bungalow system consisting of two batteries and they take around 5 minutes to charge and his home CCTV runs from 9-12 volts so it runs this and now he is sorted. If we add in the fact he gardens and is virtually self sufficient in fruit and veg and he bottles and freezes a lot and has a log burner to supplement his house heating and cook on he has it pretty well sorted and while this has taken time he can survive.

assassin wrote:Putting a 12 volt circuit into your home isn’t as daunting as many people think and as part of the prepping series I thought I had better explain this so others can install such a lighting circuit in their homes so they can run basic home lighting in the event of a power cut.

We begin with our supply and currently a large lead acid battery is the best power source as they are durable and stand a lot of abuse without complaint and they have proven themselves reliable over several years, and I would suggest the better option would be a leisure battery of around 110/115 amps capacity. These are currently the most popular size for motorhomes and caravans and leisure batteries have a better and more substantial construction to withstand heavy abuse over standard car batteries and a 110 amp battery provided gives us 1320 watts of power and a working current of 5.5 amps for 20 hours based upon the 20 hour cycle.

If we look back at previous articles we have all our calculations and how to do them and we also found that LED lighting strip came in 5M or 16’ lengths and they had cutting points every 4” and they drew 2 amps of current per 5 M length and they gave 48 X 4” pieces if they were cut into 4” lengths at their cut points. This equated to 4.8 watts of current draw per metre if we wanted our other equation and this gives our starting point for our circuit.  
Knowing our lighting strip draws 24 watts or 2 amps at 12 volts is our starting point and that it has cutting points every 4” gives us potentially 48 X 4” pieces from our 5 Metre roll and we can leave several pieces attached as long as they are 4” multiples such as 8” or 12” lengths and each 4” piece consumes 0.5 watts per 4” length. Therefore an 8” piece would consume 1 watt and a 12” piece would consume 1.5 watts as this is 3 X 4” pieces.

Next we begin the most important and critical stage and this is the planning stages as this cannot be ignored or short cuts taken if we want a true 12 volt wiring circuit in our homes and that our requirements are met for safety, convenience, and usability if we suffer a power cut. You can also make any upgrades at this stage and incorporate them into your designs as a small 12V fan may be plugged in during the summer months and they consume 5 amps so our circuits are upgraded to carry this amount of current.
We may choose not to use LED strip and build our lights from an LED cob chip for each room or use LED bulbs of 12 volts as used in cars and again we need to add up our total power consumption for all these items and stick below the 5.5amps or 66 watts draw from our battery and maintain its full capacity of 110 amps for 20 hours.

We begin our home survey by establishing the number of rooms we have and how many of them need lighting and how much light they need and how and where we are going to position our lights and for these purposes we will assume we have elected to go with our LED strip to make our lights. Obviously a kitchen and living area needs more lighting than a toilet or passage so we can allocate our lighting strips to these rooms, and this is what we need to consider, our priority areas.
Do we have a house or a bungalow? Because with any electrical circuits we adopt best practice and run these above the rooms and do drops down and for a house we heed to access the void between the upstairs floor and downstairs ceiling to run out cabling and then up to the loft through the cavity in the wall. For a bungalow it is simpler because we need to simply access the loft.

Now we need to site the battery and ensure we can charge it and I would suggest a multi mode smart charger which can charge, drop to a maintenance charge, and have a low temperature setting as batteries charge differently in low or freezing temperatures and having this capability ensures that your battery is always fully charged and ready for use. Therefore we need a covered position close to the house which has mains electricity to power our charger to charge and maintain our charger and be sufficiently well ventilated to prevent up a gas build up during charging and discharging and be sufficiently well protected from frost and freezing temperatures. I would suggest NOT having your battery in your house unless it is totally necessary as ventilating it means cold air in a house you are trying to heat and keep warm.

Now we need to look at the practicalities and realise our normal living area may change and if we have a log burner in one room other than our normal main living room it makes sense to use this room as our main living area during a power cut as it has heat and the potential to cook so lighting seems to be a no brainer.

If you don’t have a log burner and a sufficiently sized kitchen it would appear to be the best option to use this as the living area if it has a gas cooker which is being used to cook and giving off heat and these are the types of thoughts and adjustments you should be thinking of. What else would I need 12 volts for should be another question and a simple answer would be to charge a mobile phone or laptop should it become necessary and this may influence your type of charging facility and normally a car cigarette lighter would be used so why not use one. Many are rated at 10 amps so it makes sense to uprate your wiring to that above the full capacity of your total potential load and if your phone charger uses another 2 amps you need wiring of at least 10+ 2+ 2 amps so you can run your telephone and laptop charger as well as all your lighting and the next standard size cable rating above this is twin core cable rated at 17 amps so this choice is already made.

Let us look at a typical house and everyone will have to adapt this to their own home; we assume a standard three bedroom house and we can work our lighting out.

Living room containing our log burner, 2 X three strips or 12” strips for our lighting or 6 pieces.
Kitchen where we prepare and cook our food 2 X three strips or 12” strips for our lighting 6 pieces.
Downstairs passage from the front door 1 strip to provide token lighting to pass through.
Downstairs toilet 1 strip to provide enough light to see the toilet and toilet paper and wash your hands.
Porch light to see the front door 1 strip which is switchable.
Other downstairs room which is not normally used or was your main living room 1 strip for security.

If we can cut our 5M strip every 4” and give ourselves 48 pieces of LED lighting strip we can see that just to light downstairs we have only used 16 pieces of it and this is only one third of our strip so I would always suggest using a strip over our battery so we can see it.

Stairs two single strips to light the entire staircase as people have a tendency to fall on them in the dark and by lighting both the top and bottom you have them all covered.

Upstairs bathroom/toilet 1 strip to provide sufficient light.
3 bedrooms means a single strip each as you don’t really need light to get undressed and into bed so three strips.
Top landing 1 strip and sometimes it may need two lights depending upon size and layout.  

Even now we have only used 25 of our possible 48 pieces of LED strip which is just over half and if necessary we can double up on some strips to give more light to an area or we can light up other rooms such as a larder/pantry or even a conservatory as these maybe places we choose to exit and enter our home. This is useful as you can close a conservatory to house door and open a conservatory to outside door to minimise your heat losses which is beneficial if you have a log burner and it is lit to heat your home.

Now a note on security which was touched on; in the event of a major power cut in an area where every home and business has a power outage the thieves emerge and this is for several reasons:

They like the dark and this means cover for them and can go out thieving and will if they know the power will be if for a long period.
If homes and businesses have no power they will have less security and unless they have back up systems most businesses and homes will lose CCTV and their alarm batteries only have a short life of around 2-3 hours before they fail.
Any businesses with security lighting on PIR sensors will not work and they can steal anything in total darkness and not be seen or recorded and diesel fuel is apparently a prime target for thieves.

Therefore it comes down to a simple thing; you have lighting and they know that most people don’t have lighting so you must be in and if you shut your curtains and they can see a room is lit up and they cannot hear a generator they will assume or work out you have a back up system and this would likely be a power bank. If this is a power bank then your lighting is on and you have mains power and your CCTV system must be working and recording them so they tend to avoid your home and not even walk past in case your security cameras catch them doing so and basically they go elsewhere where there is now no security. Why risk getting caught robbing someone for £20 worth of goods when you can rob an unsecured business for £thousands for the same risk. If they hear a generator running it becomes a different matter as this may be worth pinching and you can suddenly make yourself a target for certain types of criminals.

Running our cables is next and to determine the route we need to make our next decision which is which rooms get 12v power and lighting and which don’t and how are we going to deal with this power to power our lights on our chosen rooms. I would suggest using a standard electrical pattress (back box) of 30mm depth and fitting them with a blank front and drilling the top with a hole large enough to fit a rubber grommet and pass your cabling through this to stop it chafing and attach a small connector plug from an automotive supplier as they are cheap and can handle 30 amps. I use something called Mini connectors as these can only fit together one way so you cannot get anything connected the wrong way round and get reverse polarity on LED lighting. These connectors work by getting the male and female plastic housings separately and the male and female connector pins in a bag which can be crimped and soldered to the 12v ring main wires and if they are crimped and then soldered with electrical solder you have a certain electrical connection.
I use 17 amp rated twin core cable as it comes in red and black and has stranded cores which can be fed into my pattress and cut, both red ends are twisted together and soldered and crimped onto my terminal followed up by soldering the crimp. And this is repeated with the black wires. I like to mount pattresses near to the ceiling to keep the wiring runs as short as possible as I can reach them but people must make their own decisions where to mount them; I also ensure several screwdrivers are around the house so in the event of any power failure a torch or head torch can be grabbed and the blank pattress front can be unscrewed one side and slackened off on the other side and the front rotated and locked open.
I prefer to make any lighting with catches or spring clamps so the cable can be plugged into the socket in the pattress and the light clipped to it and being high up means it, and its wiring is out of the way and unlikely to be hit or caught by anything. Basically it is a neat and fairly compact installation.

Once all the cabling is run through all the ground floor connections it can be run into the house cavity and into the loft for the upstairs rooms.

There are variations to this  and where some lights may needs switching and I prefer the rectangular automotive switches as a slot can be cut into the side of the pattress and the switch inserted and for a light such as porch or toilet lights, they can be switched off when not in use to save battery power. Much the same thing may happen in a bedroom where the light may be on for a short while and then switched off and possibly switched on in the night, or for stairs lights which may only need switching on for people to go upstairs.

If a phone charger is installed this is better switched as these can draw large amounts of 12v power and I would only suggest charging one phone if it is getting low and keeping it for emergencies such as 999 or 101 calls or checking on elderly or disabled family members. Remember that in a power outage any modern home phone is plugged into the mains via a transformer and if the mains is off then their home phone won’t work either and I would suggest getting any such people to switch their mobile phones on in the event of a power cut.

I would suggest having your light on at your battery because you can see it and if this light goes out it is a good clue to either your battery failing or a poor connection at your battery which is clearly visible by having, or not having your light on.

In reality you will have around 55 hours of light with a fully charged battery with all your lighting strip being constantly used and if your house is illuminated with our suggested 25 strips this would be slightly over 1 amp and the battery should last for over 100 hours. If we equate this to winter lighting then using it from 6.30am until 8.30am means 2 hours use in the morning and if it is used again from 4.30pm to 11.30pm it is 7 hours so a daily use of 9 hours and the battery should last the whole week without being charged to give us lighting.

How do we connect to our battery storage facility? Actually you can get 20mm semi rigid and flexible cable conduit along with an array of corners and angles as well as wall mounting clips and anyone with basic DIY skills can install their own 12 volt DC lighting circuit in their home.

Excellent explanation assassin, being in the motor trade, cars and now buses 12/24 v is second nature and i have done 240v ring main in my shed so for me a simple task, i would love to believe most of us on here have the basic knowledge of positive and negative for 12v and the chances of getting a shock from 12 are almost zero unless capacitors are used, which i doubt, another method for charging ‘the supply’ battery would be solar, and they do these to ‘trickle charge’ the leisure batteries( thats if they stop spraying chemtrails to block out our sun)

Be lucky all

SS

LED’s aren’t difficult to understand but while this could not be considered an in depth analysis of how LED’s work it should be considered as very basic so people can understand it and progress their knowledge. LED’s are classed as a semiconductor and are based upon something called a PN junction which works when a voltage is applied to the P section this forces the electrons to occupy a small space and compacts them in this area and if various width substrates are placed in the junction we can create something called bandwidth and this bandwidth dictates our light frequency which dictates the basis of our LED colour .

As the free electrons move through the substrate they emit energy as both heat and light and this is what gives us our light which in its basic form works from infra red on the frequency spectrum at one end to red at the other end of the frequency spectrum; we can therefore conclude that early LED’s were either infra red which couldn’t be seen by the human eye to red which could be seen.
Therefore early LED’s were either infra red and used to heat areas using the infra red emissions of the LED or as red indicators in smaller equipment and household goods and the IR heat lights became very popular in outside spaces such as smoking shelters in workplaces or pubs while the red LED’s were used in high end equipment around the home to indicate power was on.

As technology moved forwards the PN junction became modified to alter the substrate width and alter the light frequencies to give different coloured light and green and yellow light was produced by the LED and both colours became popular as red meant in stand by while green meant it was powered up. Yellow was often used as the optional colour where three functions needed indicating or identification was needed of three steps and early LED indicated battery chargers often used them as green for charging, yellow for nearly charged and charging at low capacity and red was used to indicate a problem such as connecting in the wrong polarity.

As time moved on and people became more concerned with energy and its efficiency we saw massive progress made in the field of LED’s as they produced a lot of light for very little power and they were now producing so much light output compared to previous LED’s that they were becoming viable as a genuine light source.

Incandescent light bulbs used a filament made from tungsten and this was heated until it glowed and this consumed masses of power to quickly heat it and also consumed a lot of power to maintain this white hot heat needed to make the bulb glow and provide light. These were the traditional light bulb used in houses, workplaces, and outside security lights and they worked well as industrial or commercial heavy duty variants were available and even rough service bulbs, they came with a range of outputs from very small wattages to thousands of watts and in many shapes and styles. Improvements to standard bulbs came from introducing inert gasses and while Krypton and sodium were popular the real winner was xenon and halogen as this burned hotter and used less electricity to provide the same output and became the go to bulb for many applications and car headlights were one most people would know.

Fluorescent lights became the normal energy saving light as they used fluorescent tubes which were filled with gas and coated with phosphorus powder and they had to ignite the gas and this required a small amount of mercury and once the light was lit it could stay on until it failed. Man advancements were made with fluorescent lights and one noticeable advancement was the different coating which moved from being a single phosphorus coating to a slightly less toxic triple coating called triphosphur and this improved the light output and colour. These types of lights had their problems and the main one was the powder coating was still toxic and if the glass tube was broken then people could come into contact with this coating and the mercury inside it and this toxicity was bad for their health, and disposal of them eventually required specialists to deal with the toxic substances and this cost a lot of businesses a lot of money and places such as hospitals had to account for these extra costs. Domestic households were still putting broken tubes in their dustbins and these toxic waste tubes were often going straight to landfill.

LED technologies advanced at pace but the limitations were the colour spectrum which dictated what colours could be produced, but many other advancements were also taking place and one was miniaturisation of the LED and putting it inside a casing. With light outputs going through the roof it became necessary to advance the humble LED and initially this was done by placing the PN junction on a substrate and creating an omnidirectional light in much the same was an incandescent bulb did and for lanterns this was fine for leisure applications such as camping as a set of batteries could last for weeks.

Next was the addition of a small mirror or a series of mirrors around a single chip and this helped by catching some of the wasted light and putting in a forwards direction and they began to make a single LED act like a pre focus incandescent bulb by focusing this light in a direction. This took another advancement which was to mount a single mirror under the PN junction and you could reflect this light in a very wide or very narrow angle, and all in a single LED and by using the same PN junction to provide the same light output and focus it from very wide to very narrow beams. By assembling these LED’s on a substrate you could machine manufacture LED’s without human intervention and this meant they could be built cheaply and with consistent quality in factories anywhere in the world and all without having to use skilled and highly trained staff which are expensive. Now we had the cheapest labour countries producing LED’s in bulk and the cheap overheads were reflected in their cost prices which meant they were as cheap, if not cheaper to buy than traditional bulbs and this enticed many manufacturers of lights and other illuminated products to switch from bulbs to LED power for lighting and indication.

Advancements continued and the next challenge was to produce a white light as the current white lights weren’t actually white but a variant of the current yellow LED’s which were lightened on the colour spectrum and masqueraded as whitish lights. As the LED was manufactured it was put into any type of housing and sometimes this gave problems and these were addressed by putting the completed LED’s into moulds which were filled with clear epoxy resin and this didn’t impede the light output but did make the LED tough and more durable and more importantly, waterproof. With the main electronic components now waterproof and only the wiring to the anode (positive) and the cathode (negative) terminals non waterproof it was a simple matter of soldering your supply wires to the terminals and encasing them in resin for a fully waterproof light. These lights became popular in places such as fish tanks or torches in domestic applications and in fridges/freezers in commercial applications as they used liquid cleaners to clean and sanitise fridges, particularly industrial fridges in retail supply applications such as supermarkets.

LED chips were coming in many shapes and styles and while the round ones were popular they all has their own styles and names and round ones were denoted by their outside size and their shape and a 5mm would be an outside diameter of 5mm and could come as a “dome” top, “top hat” or flat top, and even an inverted top for use inside switches.
Square and rectangular types were denoted by a number and this was their size in millimetres and the earliest standard numbered ones were called 5050 which meant they were 5mm wide and 5mm long so 5.0 and 5.0 or 5050 for their designation number and currently the 2835 is the most popular type and is 2.8mm X 3.5mm hence 2835.
Other shapes were available and oval and triangle shapes were popular as they were different and unique and could be used as pointers in LED indicators and to make letters and numbers so could be better used in LED indicator signs and were popular in vehicle mounted warning signs, particularly of roadworks.

Which came first the white or blue LED? Actually it was the white LED and it was closely followed by the blue LED for good reason, the white LED came first and used an old technology which was the use of phosphor to good effect as it was now being made with different ingredients to make it safer. In true rapid advancement style the white LED came in two colours and while they were white they were actually a yellowish white and a blueish light and are now denoted as cool white and warm white as the blue tinged LED’s are cool white and the yellow tinged LED’s are warm white.
This light is created by the phosphor coating absorbing some of the blue spectrum light and to the human eye this gives it a yellow tinge which makes it a warmer light and this is referred to in two measurements which are Joules (J) or kelvin (K) and either or both measurements can be applied to LED lighting. Both are SI units and J are an energy unit equal to 1 Newton moving 1 metre or one 3600th of a watt hour. K is the thermodynamic temperature equivalent in size to the degree Celsius.

To put this into context a bright sunny day in the middle of a UK summer the light energy is around 6450 Joules and a cool LED light is rated around 6500 joules and the warm white LED is rated around 3000 – 3500 joules.

While an LED has many benefits they also have negatives and the first one is power consumption and if we take a single LED chip and power it with the correct voltage we get the first issue and that is current consumption. If our LED chip is rated at 3.6 volts with a current rating of 30Ma or milliamps and we apply 3.2 volts to it then it should be alright shouldn’t it? Actually no because a single LED needs the correct voltage AND the correct current and if the current isn’t limited it will just suck up what is available and self destruct.
In simple terms our supply voltage is correct bot our current supply may be many amps and our LED wants them all and will take them unless we do one simple thing and that is to insert a current limiting resistor and now we have the regulated voltage and a regulated current and our LED will last for many years.
Many LED’s can be run both over volt and over current if a resistor is placed in line and many online charts exist to give the correct value resistor to use and this is soldered to the anode or + terminal of the LED and the voltage applied and the LED runs correctly for a very long time.
Times moved on again and the control electronics moved on and they got smaller and instead of a single resistor we got circuit controllers called LED drivers and these controlled the LED by measuring what it needed and applying the correct voltage and current so a single LED or a chain of LED’s ran at their maximum potential and gave a very long life at full brightness. Many now consisted of tiny integrated circuits which were totally machine made and needed no human intervention and this cheapened them and allowed them to be built in any country and utilise cheap labour and cheap overheads to keep costs down and stay competitive.

We had the scenario where the LED was running much hotter and emitting more light due to better control electronics and this raised another issue and that was the issue of heat, and more importantly, how to get rid of it so the LED ran at appropriate temperatures to preserve its life. LED life is designated in hours and this is the number of hours it will run before it drops below 70% light efficiency and if it can run for 50,000 hours before its light output drops below 70% of its original light output it would be described as a 50,000 hour LED.
If a typical LED was listed as a 30,000 hour LED it would produce over 70% of its light for over 30,000 hours before dropped below 70%.

Extending light life became paramount and it was found that core temperatures were to blame for poor light output and the degradation of the LED chip and if the core temperatures could be within sensible levels then the light chip life could be increased many fold and this theory was proven by 4X4’s. Light bars became the must have thing for the 4X4 and off roading fraternity and these were fitted on top of the front bumper or on top of the roof and both locations were in the cooling air and they had primitive cooling systems fitted and it was noted that vehicles running had longer lives than those on vehicles which were stationary and had their lights running at full power. It was also noted that LED landing lights on aircraft didn’t really have overheating problems as they were in full airflow and received plenty of cooling air and their core temperatures remained low; and they were not switched on for long periods an didn’t build up excessive core temperature heat,

In good old idiot fashion it took a non technical person known by the trade as an idiot to diagnose the problems with the LED chip and they were that the base substrate was small and the core temperatures were high and the whole lot was encased in resin so even cooling air couldn’t
circulate to cool them and he made several uneducated suggestions.
These were to make the substrate out of heat conducting material and make it large enough to conduct the heat away, remove the resin cover so cooling air could circulate and instead of mounting a single hot chip on a substrate you could mount multiple smaller ones and get more light output and all without excessive heat.
Now we had the creation of a new family of LED chips which used a much larger substrate to house multiple chips running at a lower capacity and generating less heat and all on a much larger substrate which was exposed to air and could conduct a lot more heat away. This followed on from the single chip with multiple mirrors around the outside by removing the mirrors and inserting multiple chips instead and these were called COB or chip on board and were nicknamed chip cobs which British readers will understand as the irony is an everyday saying. COB chips had another advantage which was to have their control electronics, now small enough, to be mounted on board the substrate and they could be cooled and this gave an advantage of having higher powered control chips running in both series or parallel and even series parallel and they produced more light output then incandescent bulbs.
This led to smaller and higher powered chips being fitted to fill the available space on the substrate and the same issues which has arisen with single LED chips was arising again as they were filling the entire substrate with LED chips and they were overheating. Solutions became optionally fitting heat sinks and this option was exercised by many LED light builders and they drilled and bolted the COB chip to an aluminium heatsink and coated the joint with thermal grease which conducts heat away from the COB chip to the heatsink to remove it.

Meanwhile; two camps were emerging and one camp was constantly pushing the technological boundaries at great expense with little or no returns and the other camp were looking at using this technology in another form costing a lot less and with massive returns and we had the LED strip and the 5050 COB chips with drivers all on a flexible tape. These were wired in series parallel with 12 volts being applied and a LED driver installed on the tape which drove a set or small number of these COB chips and gave optimum brightness and they had cutting points where they could be cut into sections and the LED driver would drive the COB chips. These became the basis of modern LED fluorescent replacement lights which removed the ballast and choke and the tube and replaced them with LRD’s in a more compact and smaller unit and generally the tape was fitted to an aluminium backing which also acted as a heatsink and conducted the chip heat away for a modern and sleek light fitting with an extremely long life. These lights took off massively and people could buy them as complete light fittings or just buy the LED strip and make their own aluminium backing or even buy the aluminium extrusions and plastic diffusers and build their own.
One other thing occurred and that was the use of the lens and they came in many styles and shapes and a standard generic series of lenses were made to fit certain popular sized LED COB chips and individual LED’s to provide light of different types such as focused longer range beams or very diffused light covering a very wide angle. To an extent they improved the LED in several areas and these were the longer range torches and camping and leisure lanterns used in tents and outdoor activities such as off grid camping and provide two applications in a compact and lightweight torch with dry cells or rechargeable batteries or both.
It was discovered that the focal length could be lengthened by making the torch head telescopic and this would increase the focal length and give the torch a long working range with a narrow beam and a very wide angle for inside tents or shelters and if it had different power modes it could have its power reduced to save batteries and increase battery life. Now we had the original tactical torches which would find many uses by householders, land owners, security and policing as well as general emergency services for very menial jobs such as looking under accident damaged vehicles prior to recovering them.

LED lighting now comes in many shapes and sizes and the largest market if the 12 volt market as this is the standard voltage of cars and smaller lorries as well as industrial fittings which operate on 12/24 volt systems but they operate in a range of standard and non standard voltages and can be voltage controlled from very tiny circuits which have a wide voltage input range.

Single LED's

Up to now we have dealt with LED strips because they are ideal for a beginner to start with and make basic emergency lighting as all they need is a 12 volt supply, a 12 volt regulator and the correct cable and a switch to create a simple and easy to use light during any power cut and we can take this lesson a step further fairly easily. LED strip comes with something called LED drivers and this means they take the incoming power and regulate to power the number of LED’s in their section of strip with exactly the right voltage, current, or both to run the LED’s at their optimum brightness with the best optimum longevity.

Single LED’s are even cheaper than LED strip but they require more knowledge and a little research to determine your chosen LED specifications and we have to work exactly to them and not some fairly general or generic specifications as this could under power our LED and reduce its brightness or over power it and give it a very short life.

Single or multiple LED’s can be used to replace traditional bulbs in many applications and one example would be a torch where the traditional filament bulb would have a limited life cycle of say 50 hours and run from a fully charged battery for 1 hour until it shuts down due to a flat battery. Using the same battery and an LED can considerably increase your bulb life and run time dramatically and it allows you to use something called light matching and to explain this we need to understand light and that bright daylight is the optimum light to see with and this is defined as light of 6400 Joules. The human eye works best at this colour temperature as it contains the optimum amount of blue light and the least amount of yellow light the human eye needs to react to for maximised vision and many LED manufacturers offer daylight LED’s of 6000K or 6500K which are the optimum daylight and the softer 3000K colour which contains a lot of yellow light. If you have a power cut and use LED torches of 6500K you can actually see better with much less light and while it may have 50% less lumens than a filament bulb you can actually see more with much less light.

LED manufacturers always include a data sheet and this provides a lot of critical information and is your starting point as every LED is different and this information is critical to LED designs and dictates how we work with it which begins with our circuit designs.
Our first piece of information is the shape of the LED itself along with its size as many different shapes are available and while the round LED is the most popular, they come in many popular and non popular sizes and styles; round LED’s generally come in 2mm, 3mm, 5mm, 8mm, 10mm and 12 mm and this is their outside diameter. They may come as dome tops, flat tops, or even concave tops so select what types suit your application; they also come as square, rectangular, and even triangular shapes and if a customer can place a large enough order the manufacturer will supply them; they also come in a range of colours and like many things they go through popularity phases and many will remember the blue LED’s being all the rage. With our size, shape and design concluded and in our chosen colour we can begin to decipher the manufacturers data sheet and I would recommend printing it off and putting it in your bag of LED’s so you have this information to hand and I would suggest marking the key data on your bag with a permanent marker as a quick reference in case you lose or damage your data sheet.

Our first unit to look at is our working voltage generally listed as Vf and this means voltage forwards and is the maximum working voltage of a single LED and it may be written as Vf min and Vf max and this denotes the minimum and maximum working voltage or your LED or its working voltage range.

Our second piece of information is to identify which terminal is which as LED’s are polarity sensitive and the positive or anode is specifically marked and it may be longer than its negative or cathode or if both the anode and cathode are the same length it may have a flat section punched onto the anode to denote it. Remember anode is positive and cathode is negative and this gives our next piece of information which is called Rv or Rev Voltage and a figure such as 5v or 5 volts and this is the amount of voltage the LED will stand if you connect the terminals the wrong way round and if your reverse voltage is a typical 5 volts and you wrongly connect your 12 volt battery to it then it will blow it.

Our next figure is the quantity of current or amps your LED needs and this is given as the maximum or optimum current this needs and this is given in milliamps or Ma and one milliamp is one thousandth of an amp, or 0.001 amps or 1Ma and typically most single LED’s require 20-30Ma to work.

Now we have the critical information to make our LED’s work we need other information to define our specific application and this begins with the LED brightness which can be denoted in several ways and you need to know this information. If you are using an LED as an indicator light to show power is going to something then the light output only needs to be small enough to be visible and if it is being used as a torch bulb then it needs to be much brighter to illuminate something. Next we have the working angle as this denotes the range if the light and the distance it works at and an LED indicator may require a wide working angle of 180° while a torch may require a very narrow angle of 8° which are fairly typical values. Imagine the scenario? You work in a factory and have an outside conveyor you cannot see and it has an LED running indicator which your staff need to see in a large room, such a wide angle allows the maximum visibility to as many staff as possible within that space and instant visibility quickly identifies the conveyor as not running to most people in that room. This gives the LED a wide viewing angle but very limited forward illumination as it is only an indicator and not there to illuminate something.
If we take a narrow angle of view and use out LED with an 8° viewing angle we can see it may have the same light output as our wide angle LED but it uses the emitted light differently by pointing it forwards and allowing it to illuminate something in front of it by merely concentrating the light using the internal reflector. Therefore the same LED with exactly the same specifications can be used for multiple applications simply by changing its reflector from wide to narrow angles and anything inbetween.

Now we have the basic specifications we can design our circuit and this generally means we can wire our LED’s in series or parallel or both as this has advantages which we exploit for our benefit and the longevity of the light from our LED’s and the life of the battery. The LED’s I will be using have a working voltage of 3.2 – 3.4 volts with a required current of 30 milliamps and our supply will be from a 12 volt, 5 amp battery for lightness and convenience and this will be our starting point for our figures and calculations as series wired LED’s use the available voltage without wasting it while the parallel wiring uses the current without wasting it.

We begin by stabilising our voltage with a 7912 voltage regulator in a TO22 package which is exactly the same regulator we used with our LED strip as this gives us exactly 12 volts and not the 12.4 – 12.6 volts such a battery would provide and this 40p regulator ensures reliability from a stabilised voltage. To use the maximum amount of voltage we elect to wire our LED’s in series as they use 3.4 volts and 3 X 3.4 volts = 10.2 volts from our regulated 12 volts and a series set up only draws 30Ma of current in this configuration so we are maximising our available voltage without raising our current draw. Our battery is rated at 12 volts and 5 amps or 60 watts and if we calculate it out this configuration would last for over 33 hours per amp and we have 5 amps so it will last over 165 hours or nearly 7 days continually with a fully charged battery.

One issue with LED’s is that if left they will continually draw current until they burn out which is one of their quirks and our LED’s require 30Ma and have 5 amps available which is 167 times the required current which will destroy the LED’s and the voltage of 10.2 volts requirement is 1.8 volts below our supply voltage. To control these parameters is fairly easy and cheap and our first method is to use a resistor which are around 1-2p each and we need to calculate our requirement and to do this I suggest using an online resistor chart as this just requires filling in and does the calculations for you, so first:

Select the LED’s in series.

Input voltage 12 volts
LED Forward Voltage 3.4 volts
Number of LED’s 3
Required Current 30Ma
Calculate

It really is that simple and it gives us a resistor value of 60 ohms (Ω) and we need to know about resistors next is that they come in a range of fixed values and with a range of accuracies measured in percentages and their accuracy is measured in percentages ranging from 20% and while the 20% accuracies are rare they exist. Most resistors are the 10% accuracy and their values are set so a lower set value with its 10% tolerance does not go high enough to overlap the next value resistor with its lowest 10% rating.
If we refer to our resistor chart our next lowest rated resistor is 56Ω and this is lower than our specific 60Ω so normally we would go straight to our next standard 68Ω resistor as this would suffice as these are all E12 class resistors with a 10% accuracy. If we refer to other resistor classes the E48 class has an accuracy of 2% and E96 have an accuracy of 1% and the E192 class has an accuracy of 0.5% and this can be our starting point as if we measure the resistance with our meter and our 56Ω resistor actually has a resistance of 56Ω w see our E48, E96, and E 192 classes all have a resistor of 4.02Ω.
We can take our 56Ω resistor and cut one of its leads so it is very short and select a 4.02Ω from any of the other classes and overlap the shortened leads and solder them together to form a resistor of 60.02Ω which is more than accurate enough for lighting purposes.

We could take another route and use something called an LED driver as these come in current limiting, voltage limiting, and both current and voltage limiting but they are expensive at around £5 + at the time of writing while I pay £1 for 100 resistors and £3 for a bag of 100 LED’s and we can clearly see the LED’s and resistors cost less than an LED driver. In my opinion the experts are divided between the best applications for current limiting LED drivers and voltage limiting LED drivers and both sides generally agree that the voltage and current combined drivers are better but also about twice the price. Due to these conflicting views I will stick to the current limiting resistor on simplicity and cost grounds.

Now we can create our LED network and this begins with our 3 X LED’s which we will call 1, 2 and 3 and we identify their anode or + pins and take LED 1 and bend its cathode or – pin and bend it to 90°; we take the anode pin of LED 2 and bend this to 90° and solder it to the cathode pin of LED 1. We take the cathode pin of LED 2 and bend it to 90° and the anode pin of LED 3 and bend it to 90° and solder them together and we have soldered our 3 LED’s together in series and have the anode of LED 1 free and the cathode pin of LED 3 free which will be used for our resistor and battery connections.

Next we take our resistor which may be our made up series resistor of 60.02Ω OR our next standard resistor of 68Ω and solder this to the anode of LED 1 and the other end to the battery + or positive terminal and solder or touch the cathode of LED 3 onto our battery – or negative terminal and we should have light which will last for days.

Project Torch

This project came about as one of my favourite and unusual torches gave up the ghost and stopped working and it was determined that the battery and some of the control electronics had expired and considering the use and beating it had during its life I am not surprised.

This torch began life as a high powered torch which was rechargeable and this alone was a great bonus and it had a 6v 4A/H battery and twin high powered heads each having a 6v 30 watt halogen bulb meaning each light head drew 5 amps and combined they drew 10 amps and all from a 4 amp battery, hence why it had very little working time with both heads switched on. It had an additional benefit of having a 3 LED system built into the handle which provided a useful local lighting for small areas which was useful but could have been brighter.

Work began stripping the bottom foot as this housed the original battery and its control and monitoring electronics and small LED indicators as they were for the original battery and could not be used with the replacement battery which was the same external dimensions as the original 6V battery but was 8mm longer and the electronics would foul it. Enter Paul who is a small electronics wizard and works on many things ranging from monitoring to small robotics and he is excellent and said he had a couple of lighting distributors which were modules with an LED screen which could be programmed to monitor and control up to four functions and it recharged the battery and carefully controlled this to ensure it was always at its optimum and it was my favourite price, FREE.
Next was the removal of the handle from the main head and the installation of the LED control system and the base was cut to accommodate it once all its wiring connections were made and it was actually bonded in with a special waterproof adhesive to ensure it was fully sealed as it is used outside in inclement weather and regularly got wet and the exposed soldered wires were coated in epoxy to seal them and the battery was installed, it was tight but fitted, just. Removing the original LED lights from the handle revealed a surprise as it was fitted with three small LED’s but under this reflector plate was a 3 way plate with 6 holes for LED’s which was extremely useful as I could double the number of LED’s for more local light and fit them with differing angle LED’s for better light. I had 3mm LED’s in stock and with 8°. 30° and 150° angles and they were installed as two lots of 3 LED’s and a mirror image for ease of wiring and each bank required a 110Ω resistor and I had the next standard size up of 120Ω which were soldered to each bank of LED’s and the cathodes were connected to the earth.

It was time for the first test and with the controller wires run through the handle this could be reattached to the foot and the wiring run through the handle and its trigger could be removed and wired so we fired up the new LED’s and they were amazingly bright and gave a wide angle of light which would be enough to light a medium room up sufficiently to move around and see and you couldn’t read the paper though.
With the main head removed and stripped it was time for a little more working out and both reflectors were drilled and had four 3mm LED’s with a wide viewing angle of 150° bonded in and the bulbs were replaced by a high power 10mm LED with a narrow 6° viewing angle so it had distance and localised light with very low power consumption which was far better than the old halogen bulb working time of around 5-10 minutes. With all the LED’s wired the heads were returned to their housing and wired to the three way switch which was left position left head light, right switch position, right head light and middle position, both head lights on and even with the new LED lighting heads it gave a working range of about 30 metres if bright light with a working time of over 40 hours on a full charge. With everything assembled it only remained to solder the charging wire to the waterproof jack and refit it and insert its rubber sealing plug to waterproof it and attach a 500Ma – 1000Ma charger to charge the battery and as I have a 750Ma power supply lying around it was ideal and used to plug in and charge it and it ran through various pulse charging modes and constant modes and eventually announced the battery was fully charged. If the smaller LED’s on the handle are used it would run them for a full 7 days before flattening the battery…

One of my favourite types of emergency torch are those made from readily available components and cheap and plentiful batteries and one would be the 2032 coin cell as you can get the battery holders with leads and currently a pack of 20 costs £6.99 on Amazon and this is an easy way for people to make a simple emergence torch.

You need a 3volt coin battery and a corresponding holder with leads, some pieces if thin metal strip with conducting capabilites such as standard nickel or copper strip and some rubber grommets along with a white LED of 3mm diameter and a small holderto fit it all into and I use old lathe tool tungsten tip holding boxes for mine.

You begin by opening your container and marking out your positions for everything and ensure you can get your battery case open to fit new batteries. Mark out the position of the battery holder and glue it into position leaving the leads free, mark the position of your LED and drill a hole to mount it and push it into the hole and glue it into position.

Take your negative wire from your battery holder and solder it to the negative terminal of your white LED and take your positive wire from your battery holder and solder a 1 ohm resistor to it and bend the wire on the other end into a horse shoe shape and glue this into your housing and take the anode from your LED and solder a piece of nickel strip to it and bend this into a shallow Z shape and bond this so the raised end is over the horse shoe wire of the resistor, but NOT touching it. Mark your housing directly above this and insert your rubber grommet and with your battery inserted into the battery holder you push your grommet and this should push the nickel strip onto the horse shoe and make the circuit and light the LED.

They may not be bright or pretty but in the event of a power cut they can me strategically placed around your home and they give sufficient light to see what you are doing to get around your home and other lighting.