IET announces new amendment to BS 7671 (IET Wiring Regulations)

The BS says these devices only provide "supplementary" protection they require upstream "Additional Protection"

I'd assumed that the references to "supplementary protection" and "additional protection" meant the same thing - after all BS 7671 itself used to use the term "supplementary protection" to mean what we now call "additional protection" (e.g. 16th Ed BS 7671:2001+AMD2:2004 reg 412-06 "Supplementary protection by residual current device") - i.e. I  suspect there's no more significance in the use of the two different terms than that the writers of BS 7288 haven't been entirely consistent in adopting the new vocabulary.

 

RCDs do not provide protection for upstream only downstream of the device.

Yes of course - agreed.

 

Do you agree they are not suitable when Additional Protection is required?

Well I can't really see the point in having Socket RCDs (or FCU RCDs) (or a BS for the same) if we necessarily have to provide 30mA RCD protection upstream. I can see the logic in them making (labouring even) the point that they don't provide upstream protection, hence if additional protection is required for the upstream wiring they you're going to have to make some other arrangements - but in the cases where BS 7671 doesn't demand any additional protection (by RCD or supplementary bonding) for the upstream wiring, I can't see the logic in BS 7288 demanding it.


   - Andy.

The BS says these devices only provide "supplementary" protection they require upstream "Additional Protection"

I'd assumed that the references to "supplementary protection" and "additional protection" meant the same thing - after all BS 7671 itself used to use the term "supplementary protection" to mean what we now call "additional protection" (e.g. 16th Ed BS 7671:2001+AMD2:2004 reg 412-06 "Supplementary protection by residual current device") - i.e. I  suspect there's no more significance in the use of the two different terms than that the writers of BS 7288 haven't been entirely consistent in adopting the new vocabulary.

 

RCDs do not provide protection for upstream only downstream of the device.

Yes of course - agreed.

 

Do you agree they are not suitable when Additional Protection is required?

Well I can't really see the point in having Socket RCDs (or FCU RCDs) (or a BS for the same) if we necessarily have to provide 30mA RCD protection upstream. I can see the logic in them making (labouring even) the point that they don't provide upstream protection, hence if additional protection is required for the upstream wiring they you're going to have to make some other arrangements - but in the cases where BS 7671 doesn't demand any additional protection (by RCD or supplementary bonding) for the upstream wiring, I can't see the logic in BS 7288 demanding it.


   - Andy.