Whoopsie?

[Owain]

Was just perusing the latest copy of Wiring Matters and noticed in the Earthing: Your Questions Answered article that in Fig.6 a TT installation is provided with a *whole-house* RCD.

Owain

[John Rumm]

I take it you mean that was the only RCD (i.e. no downstream ones, and it was not a high trip current / time delay type)?

[Lurch]

On Fri, 23 Sep 2005 21:15:51 +0100, Owain scrawled:

Nothing wrong with that, possibly. Could be that all the socket outlets are of the integral RCD variety.

[Owain]

The only RCD shown, and type not specified (in the diagram, or text)

Owain

[Ed Sirett]

Or it might be a simple installation of a first floor flat, not absolutely requiring socket RCD(s).

[Owain]

It would still mean an earth fault on the socket circuit would take out all the lights. IMHO this would contravene

130-02-01 All equipment shall be ...installed .. so as to prevent danger as far as is reasonably practicable. 314-01-01 Every installation shall be divided into circuits as necessary to: (i) avoid danger in the event of a fault, and (ii) facilitate safe operation, testing and maintenance.

and

314-01-02 A separate circuit shall be provided for each part of the installation which needs to be separately controlled for compliance with the Regulations *or otherwise* to prevent danger, so that such circuits remain energised in the event of failure of any other circuit of the installation, and *due account shall be taken of the consequences of the operation of any single protective device*.

from and copyright IEE Wiring Regulations Sixteenth Edition 1991. [* my emphasis *]

Owain

[Ed Sirett]

Whilst I take your point, if you extend it on it leads to the conclusion that the only compliant installation would have RCBO on all final circuits?

[Owain]

Or groups of circuits. Although in commercial premises where lighting serves eg designated means of escape or areas with moving machinery, then if RCD protection is required there is I think a case for RCBOs.

Mandating RCBOs for new installations would almost certainly save more lives than Part P.

Owain

[Dave]

What does part P mean? :-)

Dave

You do not have to answer this :-)

[Lurch]

On Sun, 25 Sep 2005 22:21:12 +0000 (UTC), Dave scrawled:

Fuck up.