Power ring mains
- Thread starter TonyS1950
- Start date
Anything is possible. Outside power is not a DIY job.
- Joined
- 27 Jan 2008
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- Llanfair Caereinion, Nr Welshpool
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As said anything is possible, what we need to know is what is there already. In the main there are few cables which can't handle 13 amp, so the quick method is to use a switched FCU (fused connection unit) as a light switch, and use a 3 amp fuse, and then to the max for the installed cable.
There are charts which show cable type, insulation method and the maximum current, many years ago using java script I made a calculator and have used it a lot to see max I can go to, now there are on line tools to do the same so in this example.
I have looked at 1mm² with a 13 amp fuse to just within the volt drop allowed for lights, and I have shown 12 meters is the max length from the consumer unit.
So start point is the loop impedance at consumer unit, and loop impedance at garage, the problem is the cost of a loop impedance meter, or any other meter which can be used to calculate the volt drop.
As to with modern LED lamps we really need to keep within 3% is some thing else, it was required when using fluorescent lights, but not so sure today.
However as @EFLImpudence says not really a DIY job, mainly due to meters required, but also in Wales building regulations for domestic dwellings.
There are charts which show cable type, insulation method and the maximum current, many years ago using java script I made a calculator and have used it a lot to see max I can go to, now there are on line tools to do the same so in this example.
I have looked at 1mm² with a 13 amp fuse to just within the volt drop allowed for lights, and I have shown 12 meters is the max length from the consumer unit.
So start point is the loop impedance at consumer unit, and loop impedance at garage, the problem is the cost of a loop impedance meter, or any other meter which can be used to calculate the volt drop.
As to with modern LED lamps we really need to keep within 3% is some thing else, it was required when using fluorescent lights, but not so sure today.
However as @EFLImpudence says not really a DIY job, mainly due to meters required, but also in Wales building regulations for domestic dwellings.
Interesting that the garage only has a lighting circuit.
When you move in , take a closer look and see what you find.
What do you want to use electrically in the garage ?
When you move in , take a closer look and see what you find.
What do you want to use electrically in the garage ?
Won't be suitable for that unless you are super lucky.
That last item opens up an entire new ball game!
- Joined
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For a wooden or other non conducting material shed it is relatively easy if total 13 amp or less, once you go over 13 amp, or you use a metal clad anything we move into a completely new ball game.
Basic fact most garden tools are class II electric, battery, or two stroke petrol, once one starts to look as class I this starts to open up other considerations. Also any heat pump be it heating or cooling unless supplied from an inverter is very dependent on volt drop, and also ambient temperature. So add a freezer to the shed items and again things change.
But without the prospective short circuit current (PSCC) or the loop impedance between lives (line and neutral) one can't really say what is within the supply cables already installed, and of course details of the supply cables.
Back in around 2002 my son was wiring houses, there was a twin and earth inside the house, and a steel wire armoured outside to the garage, looking at garage side one would say that will take well over the 6 amp MCB installed, but looking at the consumer unit side, it was a different story, so with that in mind the info given is not enough.
Basic fact most garden tools are class II electric, battery, or two stroke petrol, once one starts to look as class I this starts to open up other considerations. Also any heat pump be it heating or cooling unless supplied from an inverter is very dependent on volt drop, and also ambient temperature. So add a freezer to the shed items and again things change.
But without the prospective short circuit current (PSCC) or the loop impedance between lives (line and neutral) one can't really say what is within the supply cables already installed, and of course details of the supply cables.
Back in around 2002 my son was wiring houses, there was a twin and earth inside the house, and a steel wire armoured outside to the garage, looking at garage side one would say that will take well over the 6 amp MCB installed, but looking at the consumer unit side, it was a different story, so with that in mind the info given is not enough.
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