1.5 mm cable - replace with 2.5 mm

dal · 8 Jan 2014 at 10:47

Hello, I want to move a plug socket a couple of feet, away from the direction the cable is feeding the plug socket from. I'm going to replace the section of cable between this plug socket and the one before.
It currently has 1.5 mm T & E cable which I want to replace with 2.5 mm T & E . (The cable running to the socket before the one I want to move is 2.5mm.)

Can someone just confirm this is ok, I mean it's ok to have a cable that can carry more current than what will pass through it but not the other way round.

BTW this is a radial circuit on a 16 AMP MCB, so no returning cable.

robj20 · 8 Jan 2014 at 10:50

Its fine to go up in size.

dal · 8 Jan 2014 at 13:30

Ok cheers.
Another question - the cable is going in hardwall/ plaster does it need to go in conduit or is it ok being cable clipped to the wall ( block )

StevenG · 8 Jan 2014 at 15:04

dal said:
Ok cheers.
Another question - the cable is going in hardwall/ plaster does it need to go in conduit or is it ok being cable clipped to the wall ( block )

clipped is fine if its being covered up by plaster etc, if not then it needs to be done within conduit.

russ9898 · 8 Jan 2014 at 16:23

StevenG said:
clipped is fine if its being covered up by plaster etc, if not then it needs to be done within conduit.

Sorry, but that is incorrect.

The cable does not need to be in conduit if recessed in the plaster however it is advisable to put a layer of capping over the protect the cable whilst re-plastering.

More importantly, if making alterations you need to ensure the recessed cable is protected by a 30ma RCD.

dal · 8 Jan 2014 at 16:34

Its on a rcd protected circuit.
Thanks.

StevenG · 8 Jan 2014 at 16:38

my post said that if its not being burried then it needs to be in conduit/trunking.

doesnt need to be protected if being plastered over clipped is fine

Tesla · 9 Jan 2014 at 05:06

Some sort of mechanical protection from the sharp edge of a plasterers trowel is a wise move. PVC capping is very cheap so ideal. Oval conduit is another quick and cheap option.

Millwall.FC · 11 Jan 2014 at 22:09

2.5mm cable is the correct size for the protective device being used if you have any existing 1.5 in this circuit it should be replaced with 2.5 or your RCBO down rated to 10A. Since the circuit is RCD protected you can have the cable any buried vertical/horizontal depth you want. as tesla said capping is good practice to protect against the corrosive plaster on the cable sheath (many materials degrade T+E sheaths over time) it also provides minimal mechanical protection but nothing stopping you just from clipping it.