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[fisha]

Hi guys just looking for advice on supplying a second consumer unit in a house for a garage. The electrician has supplied a second consumer unit for a garage using a 10mm squared cable taken from the top of the 63A main switch fuse from the Consumer unit in the house. The 10mm square cable is then feeding a 40amp MCB in the garage off which has 10amp MCB for lights AND RCD for sockets. I was just wondering is this the best way to supply a second consumer unit and is it possible to have a second consumer unit with a 63A main fuse. If so where is the best place to supply it from in the main consumer unit, top or bottom of the 63A main switch fuse.

Cheers

[ericmark]

In a house you have Part P regulations which means you have to pay LABC at least £100+ vat. Also it will have to be to rule book which means unless your supplier has given you a separate isolator then you will also have to pay for two visits from supplier to disconnect the re-connect supply.

I would consider it is not cost effective to DIY this work.

Main incoming fuses are normally 60, 80 or 100A so since you say 63A I think you have fuse and isolator mixed up.

In most consumer units the largest MCB is 50A and I would consider that ample to feed a garage. If you need more than 50A then you should consider a second supply but this will be expensive.

One is permitted 3 meters before a fuse if protected there is a whole list of conditions but 10mm would normally only be considered OK for 45A not 63A it is not plane what you have but one hesitates as it seems you may already have something which is not correct which any LABC is likely to pick up on and demand to see paperwork so I would consider getting an electrician who is a member of a scheme to do the work as he is able to sign off what he had done without calling on the LABC.

[fisha]

Thanks eric, im living in ireland. main tails coming in are fed into the supply boards main fuse which is 80A.then into the meter and from the meter into the consumer unit which has a 63A main switch fuse. The electrician ran a 16mm2 cable from the top of this fuse into the garage supplying another fuseborad is this proper practice or should he have used a henley box to split the incoming supply. thanks