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Posted By: Adam_151 I think I'll have a bath instead.... (UK) - 01/15/09 11:13 PM

This is a scan someone else took from a trade magazine

Our 'regs'(code) now requires electric shower heaters to be RCD (GFCI) protected* ... but this kind of defeats the purpose a little :P

[Linked Image from electrical-photos.com]

* it always was strongly recommended.

Posted By: Trumpy Re: I think I'll have a bath instead.... (UK) - 01/27/09 01:52 AM
Hmm,
Not good at all, 40A breaker on a length of 6mm˛?.
Makes you wonder where people learn to do things like this.
Hey, it could be worse (the cross section thing) - the POs ingenious sparky used bus bar for the phases and jumpered the neutrals (switched neutral MCBs) with wire links - 2.5mm2 for 35 amps. Needless to say I used 6mm2...
IMO the RCD device should be in enclosed box to prevent the water get into the RCD device.

Here in France, yes we have to run them on RCD the old code did not need the RCD if hardwired but now it don't matter which way it hook up.

6mm2 ? with 40 amp OCPD there if very short run yeah it will work however IMO just boost it to next size larger conductor 8mm2 will work fine { if ya can find this size }

Merci,Marc

Posted By: Trumpy Re: I think I'll have a bath instead.... (UK) - 02/09/09 02:36 AM
With a 40A MCB on the circuit, you'd need 10mm2 cable.

The CB is installed to protect the cable, not what is on the end of it.

Common sense would tell you that that RCD unit should be installed at the start of the circuit, not the end of it, otherwise only half of the circuit is being protected.
Posted By: LarryC Re: I think I'll have a bath instead.... (UK) - 02/09/09 07:44 PM
Common sense would tell you that that RCD unit should be installed at the start of the circuit, not the end of it, otherwise only half of the circuit is being protected.

Common sense? shocked

Does it look like common sense was even in the room at the time of installation?
Interesting... my table (Austrian code) says cable embedded in masonry 6mm2 is good for 40 amps. Wire in conduit is slightly lower in capacity, the table doesn't list anything beyond 25 amps single phase, but for 3 phase (again lower capacity) 6mm2 is only good for 35amps.
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