Buried cables, RCDs, new CU.

[Risteard]

The new work is replacing a distribution board; is there a regulation which states that distribution boards, new or otherwise, must contain RCDs?

I know that, but you are still connecting the final circuits to that distribution board, ergo selection of an appropriate protective device is part of the work of replacing the distribution board.

 

[kai]

Yes, an RCD or two are compulsory in all new or replacement DB's, unless other methods like SRCD's are used.

 

[Iggifer]

Yes, an RCD or two are compulsory in all new or replacement DB's, unless other methods like SRCD's are used.

By SRCD? Do you mean socket with an integral RCD? How does that get over the issue of buried cables?

Particularly as the OP said RCBOs were already protecting socket outlets

 

[kai]

No, the only way round is to install a socket circuit (radial or ring) with metal clad RCD type sockets, and wire them in SWA (surface mounted) to the metal consumer board. (It has to be three core SWA, one of the cores being the earth, not reliant on just the earth bonded armouring wires.)

 

[Adam_151]

(It has to be three core SWA, one of the cores being the earth, not reliant on just the earth bonded armouring wires.)

Aside from the fact that you appear to be answering a different question than everyone else.... Why? Correctly terminated the armour is fine as a CPC (as long as all the usual design considerations are properly considered)

Let me guess... It must also be a Wylex Metal clad board....

 

[EFLImpudence]

not reliant on just the earth bonded armouring wires.)

Not bonded in our meaning of the term - just earthed - why not?.

 

[Risteard]

(It has to be three core SWA, one of the cores being the earth, not reliant on just the earth bonded armouring wires.)

Aside from the fact that you appear to be answering a different question than everyone else.... Why? Correctly terminated the armour is fine as a CPC (as long as all the usual design considerations are properly considered)

Let me guess... It must also be a Wylex Metal clad board....

Indeed, and there are other options also (e.g. surface conduit; flush steel conduit; MIMS etc.)

 

[ban-all-sheds]

They might well say that, and for the reason you suggest. but where (if anywhere!) does that process stop.

How about at the point at which you are no longer responsible for what the installation is like when you are done?

Would they suggest that every aspect of every final circuit had to be fully compliant with current regs in order for a CU change to be certifiable as 'compliant'?? If they really wanted to be silly, I suppose they could even say that 'old colours cable' in any of the final circuits renders the CU change 'non-compliant'!

Well - if you want to talk about silliness, how about not drawing a distinction between what you're not installing and what you are?

Cable colours, routes etc are nothing to do with you, but the circuit protections you are installing are. In just the same way that you would not replicate, say, a 63A breaker for a 2.5mm² socket radial but would ensure that that part of the circuit, i.e. the part for which you are responsible, was correct, you would ensure that RCD protection was likewise.

I know that, but you are still connecting the final circuits to that distribution board, ergo selection of an appropriate protective device is part of the work of replacing the distribution board.

 

[Iggifer]

No, the only way round is to install a socket circuit (radial or ring) with metal clad RCD type sockets, and wire them in SWA (surface mounted) to the metal consumer board. (It has to be three core SWA, one of the cores being the earth, not reliant on just the earth bonded armouring wires.)

As has been pointed out. Not only are you not answering the question, but that's not even strictly true.

Not even close to the only way to do it. And why bother going to all that trouble and expense, when you could just fit an RCBO at source? I know which option I'd choose

 

[Spark123]

I don't follow why SWA would need to be surface mounted either.

 

[kai]

A Proteus or Chint metal board would do just as well, as some electricians really love them (NOT ME!).

 

[Iggifer]

HA. Funniest thing I've read this week.

 

[stillp]

A Proteus or Chint metal board would do just as well, as some cheapskate charlatans really love them (NOT ME!).

There you are Kai, fixed it for you!

 

[JohnW2]

Cable colours, routes etc are nothing to do with you, but the circuit protections you are installing are. In just the same way that you would not replicate, say, a 63A breaker for a 2.5mm² socket radial but would ensure that that part of the circuit, i.e. the part for which you are responsible, was correct, you would ensure that RCD protection was likewise.

I can understand that viewpoint, but how can it work in practice? How exactly is the person who has been engaged just to do a DB change meant to know which circuit(s) (if any) involve cables buried <50mm in walls (and without earthed sheaths or mechanical protection), hence requiring RCD protection per current regs??

Kind Regards, John

 

[Iggifer]

A Proteus or Chint metal board would do just as well, as some cheapskate charlatans really love them (NOT ME!).

There you are Kai, fixed it for you!

The more he posts, the more I suspect he's just trolling us, at least 50% of the time