Date   : Mon, 14 Sep 2009 21:59:03 +0100
From   : pete@... (Pete Turnbull)
Subject: Leccy @ Acorn World '09

On 14/09/2009 08:33, Phil Blundell wrote:
> On Mon, 2009-09-14 at 00:19 +0100, Pete Turnbull wrote:
>> I know about the cable protection, but I didn't think RCD protection was 
>> mandatory for *all* sockets

> You're right, I was over-generalising a bit there.  The actual
> requirement of Regulation 411.3.3 is to provide RCD protection for all
> "socket-outlets with a rated current not exceeding 20A that are for use
> by ordinary persons and are intended for general use".  This is
> considerably broader than the requirement of the 16th edition; I don't
> have the text to hand, but it was something along the lines of RCDs
> being necessary for any socket that outdoor equipment might foreseeably
> be plugged into.

Ah, that makes sense.  I don't have a copy of either set of regs so I 
was only going on what I'd been told by others and seen in various 
guides (some of which are heavier than the regs, if a bit less 
expensive!).  I do remember the bit about outdoor equipment, and so 
/most/ of the sockets on our second consumer unit, installed about 8 
years ago, are on the RCD side.  That's all the ones in the utility room 
near the back door, and all but one down one side of my workshop, but 
that one and all the ones on the other side (where most of the IT 
equipment lives) and the Commando sockets are on the non-RCD side (and 
are a different colour so you can tell which are which).  All the 
sockets on the other, original, consumer unit (20 years old) are 
RCD-protected.

The RCDs at work are a little different to domestic ones: settable to 
30mA/100mA/300mA/1A/3A trip and 
30ms/60ms/two-other-values-I-can't-remember delay time :-)

-- 
Pete                                           Peter Turnbull
                                               Network Manager
                                               University of York