Need to identify supply to garage

[rubble2]

I have a detached old timber garage that I want to demolish and re-build in brick. I need to identify the supply to the garage at the electric meter / fuse box in the house, then temporarily cut off and make safe the supply, until the garage is rebuilt. My house has 2 separate fuse boxes and I don’t know which one feeds the garage – a bit of investigating is needed.
would it be expected that the garage would have its own supply of the CU or is it possible that it may be just run off the downstairs ringmain.
Obviously, if it has it's own supply it will be much easier to isolate it, I guess if the supply is shared, then the cabling will need to be traced in order to isolate the garage supply

 

[rebuke]

It is likely that one of four things will have been done:
1) The garage is taken as a spur of the ring main
2) The garage has it's own separate feed from one of your CUs
3) The garage is directly on the ring main
4) The garage has it's own feed directly from your meter

Only way you're really going to find out is to either trace the cabling, or turn off circuits one by one until it loses power. That will determine whether it's 1/2 or 3 (and if you can't turn it off then it's probably 4). The steps to remove it temporarily will depend on how it is connected.

Remember that when you come to reconnect it, any work you do should be compliant with the latest version of the wiring regs, and the existing cable might not be compliant etc, so it may not be a matter of just reconnecting it afterwards.

If you have to run a new cable to it, then that will definitely be notifiable under Part P (as it's a new circuit, even if it's similar to an old one). Reconnecting it if everything at the other end has changed may also count as a new circuit...

 

[Adam_151]

Could be either mate, one would hope that if its off the ring final, then its from a fused spur (but if its been bodged it might not be!)

What size and type of cable does the supply enter the garage through? could give you some clues.

Otherwise, shut down computers etc and start pulling fuses until you get the right one, and if you ahven't cut anything else off, then disconnect at source, if you've cut something else off, its more fun and games..

When you build new garage, put in some civils duct with a rope in it to enable a new supply to be pulled into new garage, also bear in mind when you call a sparky to install electricity to new garage, then its possible your house may need some remedials (possibly new protective bonding and board change)

 

[EdwardCurrent]

Hello Rubble.

I would have thought that the shed had it's own supply, although it may well be fed from the downstairs ring as you mention.
No markings at the fuseboard ?
It would be a good idea for you to use this time to mark up the whole C/U, as I think you will find it's 'source' by turning individual circuits off, one at a time etc.
Do you have a voltage tester ?

When it comes to re instating the 'electrics', I think you may run in to Part P. Might be an idea to look into that now.

Ed.

 

[rubble2]

Thanks for all the pointers, plenty for me to look at there.