Comms room

[eddielarge]

By your interpretation of the regs twin RCD CU's are not compliant with 17th edition and only RCBO's will suffice.

no ,, by installing a twin rcd you are trying to minimise so not sure of your point ,, apart from being picky

 

[pevvers]

By your interpretation of the regs twin RCD CU's are not compliant with 17th edition and only RCBO's will suffice.

Yep, if you go to the letter of the regulations I agree. RCBO's are the only way to fully comply with the regulations when installation methods, circuit types and use of installation by ordinary persons has to be followed.

But as we all know, sometimes you have to read between the lines with the regs, and the term "minimising" can be covered by installing two RCD's, with the circuits in the same areas split between the two. A front end RCD with no discrimination further down for no particular reason will not comply with 314.1 (i).

If this is a commercial installation then there may be no specific reason why 30mA protection is needed if cables are not unprotected and buried in walls. If the ring mains only supply comms equipment the I would suggest they were under the control of skilled or instructed persons. Also the fact that IT equipment has high earth leakage currents, I would use another regulation (not got my regs with me at the mo, but I'll look it up) to bypass the requirement for additional protection for the sockets by 30mA RCD anyway...

But as always, everybody has their own interpretation of the regs,

 

[Notsosmart]

no ,, by installing a twin rcd you are trying to minimise so not sure of your point ,, apart from being picky

Not tryimg to be picky, just pointing out that interpretation can be open to debate. It could be argued that giving a code 4 is being picky.

If, as this Dist board appears to part of a system within a factory enviroment with other dist boards dotted about then it could be argued that minimising inconvenience has taken place already (lighting circuits isolated from power etc) & yes I realise that having comms supply within the same board as hand driers could cause nuisance tripping but really it is down to you the inspector to determine whether this is a factor and by asking the person ordering the work if tripping does in fact occur, that is why I changed my opinion during the thread form none to possibly code2 to code4 back to no code, having considered the various facts you have drip fed us.

Yep, if you go to the letter of the regulations I agree. RCBO's are the only way to fully comply with the regulations when installation methods, circuit types and use of installation by ordinary persons has to be followed.

But as we all know, sometimes you have to read between the lines with the regs, and the term "minimising" can be covered by installing two RCD's, with the circuits in the same areas split between the two. A front end RCD with no discrimination further down for no particular reason will not comply with 314.1 (i).

If this is a commercial installation then there may be no specific reason why 30mA protection is needed if cables are not unprotected and buried in walls. If the ring mains only supply comms equipment the I would suggest they were under the control of skilled or instructed persons. Also the fact that IT equipment has high earth leakage currents, I would use another regulation (not got my regs with me at the mo, but I'll look it up) to bypass the requirement for additional protection for the sockets by 30mA RCD anyway...

But as always, everybody has their own interpretation of the regs,

Thanks Pevvers you must have answered whilst I was typing, I wasn't being critical per-se just playing devils advocate. Unfortunately the only way to fully determine the correct course of action is by viewing the installation for ourselves.

I also agree (and have done within the thread) that the power to the comms should never have been within the same board as the hand-driers and I too I wouldn't have it controlled by an RCD. But to code it? Not so sure, an advisory note certainly, a discussion with the relevant person most definitely.

 

[pevvers]

Thanks Pevvers you must have answered whilst I was typing, I wasn't being critical per-se just playing devils advocate. Unfortunately the only way to fully determine the correct course of action is by viewing the installation for ourselves.

I also agree (and have done within the thread) that the power to the comms should never have been within the same board as the hand-driers and I too I wouldn't have it controlled by an RCD. But to code it? Not so sure, an advisory note certainly, a discussion with the relevant person most definitely.

Indeed, it is still a matter for contention with whoever is doing the report. But from the little bits we know I would still come to the conclusion that it does not comply with the latest edition of the regulations, although not unsafe...

 

[Guest123]

A code 4 at most, I feel.