Submain Supply 100a 100mA

[westward10]

PME

Why the need for rcd protection.

 

[Andy78]

Out of interest ive never had to terminate a 25mm cpc into a cu, do you just fork it into two earth bar holes?

Un-insulated Reducing Pin - SWA - http://www.swaonline.co.uk/cable-terminations/copper-pin-terminals/uninsulated-reducing-pin

 

[Tom Christopher]

We can only confirm if this is okay if you let lose what the earring system is.

PME

Why the need for rcd protection.

So would you happy to run say a 16mm 3C swa from a 63a isolator to the consumer unit? No need for any RCD on the supply and above a ceiling/under the floor?

 

[westward10]

Yes providing the armour is effectively earthed. Additional rcd protection is not required and an s type 100ma rcd does not provide additional protection anyway.

 

[Des 56]

PME


So would you happy to run say a 16mm 3C swa from a 63a isolator to the consumer unit? No need for any RCD on the supply and above a ceiling/under the floor?

Why are you making reference to floors,ceilings and Rcd when considering swa

 

[Deleted member 26818]

Hoops or studs?

Why are you making reference to floors,ceilings and Rcd when considering swa

probably because it’s one of the acceptable methods for providing the extra protection required.

 

[DPG]

Why would it need that? Nothing in BS7671 about it, and the DNO may not specify it.

No, but as you know it's a common and well-known requirement.

 

[Wilko]

Hi - please confirm suppliers fuse, installation load, Ze, cable distance and installation method etc. Otherwise they're all going to argue pointlessly .

 

[Zdb]

My understanding is that the DNO will not generally allow their fuse to be used to protect any part of a consumer’s installation.
The 3m stipulation relates to the BS7671 requirement that overload protection must be provided within 3m of a reduction in the CCC of a conductor.

Where can I find this 3m rule in BS7671?

 

[Deleted member 26818]

Where can I find this 3m rule in BS7671?

Sections 433.2 and 434.2.

 

[Zdb]

Thanks