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[ant1]

Hello all,

I've just bought a very small ground-floor flat in a newly-built property. I'm amazed that the paperwork for the electrical wiring states quite unequivocally N/A wherever RCD/RCBO, leakage currents etc are mentioned.

I'd thought that _all_ new wiring had to include at least one RCD? I can understand a relaxation for wiring planned before a couple of months ago, perhaps, but surely there should be an RCD?

Regards Ant

[ericmark]

Where planned before July 1st then they do not have to comply with new regulations. And with projects like Olympic stadium they could still be working on 16th edition in 4 years time.
However the 16th did say where it is likely to be used outside sockets should be RCD protected so to have no RCD in the flat it would have no outside area not even a possibility you may hover the car which is very unlikely.
Eric

[ant1]

Hello Eric,

Thankyou - I'd thought the 16th also called for an RCD as we could still get a kettle fault by the sink. And as a practical type I could certainly have a mains lead trailing outside as it's ground-floor. But as a practical type I'd still RCD it anyway!

Regards Ant

[ericmark]

I fitted duel RCD protection to my house in 1991 and I think it is a good idea. When we got any faulty equipment it was soon apparent which one was causing the problem and the items of equipment have slowly grown. I can see where one may have multi faulty items it can cause problems. but within a couple of months all faulty items are identified and then all runs smooth so I am fully in favor in all people following my example.
But I was considering you were likely to go to builders and complain so I was not saying what I think should happen but what the BS7671:2001 regulations required (16th Edition covered both BS7671:1992 and BS7671:2001).
So anything designed before July 1st 2008 needed RCD's to protect any sockets likely to be used outside. Also sockets in a bedroom where a shower is installed, and locations of increased shock risk like electric showers etc.
Now this is increased to cover cables buried less than 50mm all sockets under 20 amp rating and everything including lights in a bathroom.
So since they need to re-design as there was an error in original design then the new design will have to include RCD's on all circuits to 17th Edition also called BS7671:2008.
If you need details to show your builder then I can give you numbers.
All best Eric

[ant1]

Hello Eric,

Thankyou very much, I'll have an agitate but as we've now bought the place it may be an uphill struggle; outside extensions though are certainly likely. I expect them to argue mightily especially in the current economic climate...

As an aside, the place we've recently bought to live in (the flat was a result of severe downsizing!) had bad nuisance tripping of the RCD, taking out all the main circuits except the lights and smoke alarms - two or three times it happened before we'd moved in. Three of the four bungalows here were all doing it. After much too-ing and fro-ing and sucking of teeth the supplier investigated, found the fault current was 6mA which is apparently at the high end of expectations while the RCD was both as fast as it could be and as sensitive as it could be while remaining within tolerance. I had the devil's own job persuading anyone to do anything and quite honestly the electrical people knew virtually nothing about modern RCDs...

It's a good job I enjoy moaning!

Thankyou again -

Regards Ant