Wire Size From Rcd To Breaker Box ( Consumer Unit ).

[thaibeachlovers]

Finally got the mains wire connected to my Safe T Cut RCD. However, the electrician didn't have any large diameter wire to connect the RCD to the breaker box. So I gave him some spare 2.5 mm wire.

Does that matter, or do I need some heavier gauge wire? The mains wire into the house looks like 10mm. The wire length is about 2 feet from RCD to breaker box connection.

Thanks for advice.

BTW, don't let anyone say that there's an unemployment problem for electricians- took my wife months to find someone to do the job!

PS. Though the lecky did wire up the mains wires correctly ( with my "help" ) he managed to transpose the wires for the lights with the one from the shower heater- so the shower is currently on a 10 amp breaker, and the lights on 20- sigh.

[Crossy]

What is the rating of the breaker that the Safe-T-Cut is connected to? That would probably be the main switch.

If the incoming is 10mm then you should use 10mm from the RCD to the board.

[thaibeachlovers]

The main switch has 50 written on it, so presume 50 amps.

Thanks for the reply ( that was quick ). I guess I'll have to pay for a meter of 10mm then.

Thanks to the delights of those wooden boxes they use here, I'll have to pull it off the wall again.

Still, at least now I can switch off the mains, without having to pull the live wire out of the meter box, so I won't have to pay someone to do a job I'll have to redo as soon as he's left the house!

The whole wiring system in the house is a bit dodgy, so it's great to finally have some protection.

[Crossy]

10mm on a 50A breaker will be fine.

[regedit]

Some of those wooden box's have hinges on them so you only need to open one side and the door will swing open to allow access to the back. Watch out for the gecko who's already set-up home in there.

[thaibeachlovers]

Some of those wooden box's have hinges on them so you only need to open one side and the door will swing open to allow access to the back. Watch out for the gecko who's already set-up home in there.

I'm never so lucky! The box I have is nailed to the wall, and the mains wire was clipped behind the box, so no way to pull wire out without levering the whole box off the wall. At least there was enough spare length to actually reach the new RCD though.

[thaibeachlovers]

10mm on a 50A breaker will be fine.

Thanks Crossy.