My living room sockets which are on a ring main circuit (all sockets run off a single 32amp breaker) are all connected using old imperial cable (2.5mm is the equivalent).
I want to move a socket higher (not spur) so I plan on removing the socket and using Wago inline connectors to extend new cable so it runs up the wall to a new socket.
Question is given the earth (CPC) cable is now 1.5mm and I'm told the old imperial earth cable is 1.0mm, can these earth differing sizes be used on the same circuit? I've did a new socket as a spur about 8 years ago and have never had any issues?
Some common errors with DIY alterations to sockets that I come across all too often are where the persons doing the work assumes;
(a) Sockets must be wired as ring..... they do not!
(b) Sockets must wired with 2.5mm T&E.... they do not!
(c) Sockets must be supplied by a 32A MCB.... they do not!
(d) Because there are two cables connected at a socket or an MCB then it must be a ring.... it may not be!
(e) Because something is working it must be good, safe, and electrically robust enough to be extended.... it may not be!
Whereas reality is more like:-
A 4.0mm 32A radial, or a 2.5mm 20A radial may be a better, more economical and safer solution for many socket circuits.
A broken ring circuit can appear to work but it leaves many potential dangers, and it should never be amended / extended without first confirming the ring integrity and correcting all anomalies found prior to doing any alterations.
For many years now there has been talk of removing ring circuits from the wiring regulations.. There are very much a UK oddity, and there are safer more practical wiring arrangements for sockets that can be used.
Very few people undertaking DIY electrical work have any knowledge of the importance of a circuits "Earth Loop Impedance" and the maximum permissible values to ensure that the circuit protective devices will operate fast enough.
The size of the live conductors and the earth CPC have direct effect upon the Earth Loop Impedance.
So..
{A} If you have proved that the ring is intact and it is within the max Earth Loop Impedance values then mixing the 1.0mm & 1.5mm should not be a problem...
{B} If you circuit is only providing a handful of low power requirement sockets, then you could be better converting it to a 20A radial and save yourself all the faff of extending & testing the ring! (Excluding Kitchens and Utilities, very few rooms in the average domestic house actually need a 32A socket circuit!)
Please also remember Wago's are great.. But they do all have a maximum current rating they are designed to operate with..
NOT all Wago's have the same current rating!
Choose your Wago wisely!
