RCD protection of Partition cable

[edunt]

Hi - about to have some wiring done and was just contemplating how it will be done and what it will look like afterwards.

Part of it will be a ring extended along the length (inside) of a new partition wall being built to a double socket, and the back again to continue the ring.

Mention was made of an RCD needed to protect this cabling under the latest rules so I looked it up. I see this:-

A cable concealed in a wall or partition must

a) be at least 50mm from the surface [note 1]

b) have earthed armouring or an earthed metal sheath (eg SWA, a BS 8436 cable or MICC cable)

c) be enclosed in earthed steel conduit or trunking

d) be provided with mechanical protection (3mm steel is deemed sufficient to meet this requirement)

OR

e) be installed in a safe zone .

The 17th edition also requires cables in the safe zone to have 30mA RCD protection if not installed as per a, b, c or d.

Note 1 - If the wall or partition is made from or partially made from metal then the cable will require RCD protection or be installed as b), c) or d) above​

Raised a couple of questions with me, so I thought I would ask those that know (as my electrician is on holiday at present)....

1) why isn't the RCD in the CU good enough?

2) Since it is a ring, does it therefore need an RCD in EACH of the cables before it gets to the partition wall?

Thanks Ed

 

[Risteard]

(as my electrician is on holiday at present)....

They usually are - especially in October.

 

[flameport]

1) why isn't the RCD in the CU good enough?

It is, provided it is the correct type.

2) Since it is a ring, does it therefore need an RCD in EACH of the cables before it gets to the partition wall?

No, and let's hope the electrician really is on holiday.

 

[securespark]

Who mentioned the RCD was needed to protect this cabling? If it was your electrician, then sack him immediately because he raises doubts he knows the regulations. Anyone properly qualified would know exactly what the regulations are, what is needed to comply with them and how to adapt your installation if it does not currently comply.

If you do not genuinely have a proper qualified electrician (not a DIY'er or a builder who claim to be qualified), then get one ASAP.

 

[edunt]

mmmm. Ok thanks guys. I didn't check his credentials - perhaps I ought to then. He was someone I got from a local advertisement.

He said he had to go to USA to see some relative or other.

I will get someone else then, to have a second opinion.

Thanks again

 

[seasickstevie]

Let's know what the next guy says.

 

[sparkwright]

What's the problem here?

All the electrician has said is that the new sockets should be RCD protected.

Though if there is already an RCD that will protect these sockets/wiring then that should be enough. It needs to be 30 mA.