RCD protection in an IT run office

Going back to the original question - my thinking would be along these lines...


Current BS 7671 requirement is for sockets rated 32A or less to have 30mA additional protection - unless (for non-domestic premises) there's a documented risk assessment that concludes that additional protection is not necessary.


So first ask if there's a suitable RA. If so, all is fine.


If not, it's a non-conformity. How serious that is depends on the circumstances. I reckon an office environment is pretty similar (if not safer) than a domestic one in this kind of respect - so I'd probably code it in a similar way. Remember that the RCD is there to guard against high Zs after the socket (e.g. long outdoor extension leads) and accidental damage that exposes conductors (e.g. cutting through flexes with lawnmowers or plugging in seriously damaged equipment). Normally we'd code lack of 30mA additional protection for sockets as a C3 if the socket is only intended to serve interior areas, or C2 if serving outdoors (which might include an indoor socket if it looks like it might be used for feeding equipment outdoors). You might want to adjust that a bit for an office environment - e.g. if office policy is that people can't bring in their own appliances and there's little outdoors that would need a portable electricity supply (landscape maintenance contactors tend to use 2-stroke tools rather than electric and extension leads), they you could possibly afford to be a little more relaxed.


   - Andy.

Going back to the original question - my thinking would be along these lines...


Current BS 7671 requirement is for sockets rated 32A or less to have 30mA additional protection - unless (for non-domestic premises) there's a documented risk assessment that concludes that additional protection is not necessary.


So first ask if there's a suitable RA. If so, all is fine.


If not, it's a non-conformity. How serious that is depends on the circumstances. I reckon an office environment is pretty similar (if not safer) than a domestic one in this kind of respect - so I'd probably code it in a similar way. Remember that the RCD is there to guard against high Zs after the socket (e.g. long outdoor extension leads) and accidental damage that exposes conductors (e.g. cutting through flexes with lawnmowers or plugging in seriously damaged equipment). Normally we'd code lack of 30mA additional protection for sockets as a C3 if the socket is only intended to serve interior areas, or C2 if serving outdoors (which might include an indoor socket if it looks like it might be used for feeding equipment outdoors). You might want to adjust that a bit for an office environment - e.g. if office policy is that people can't bring in their own appliances and there's little outdoors that would need a portable electricity supply (landscape maintenance contactors tend to use 2-stroke tools rather than electric and extension leads), they you could possibly afford to be a little more relaxed.


   - Andy.