EICR Code for metal light switches with earth to backbox

[Ian1981]

Class 1 exposed conductive parts require earthing, if it’s earthed In situ then it’s no code.
best practice is to earth the plate directly however i dont see the issue if it’s earthed full stop by one way or another.
The regulations will not tell you how to earth it other than it requires earthing.

 

[westward10]

The instructions with the accessory will demonstrate a cpc to the front plate.

 

[Dartlec]

That’s a good point, I hadn’t thought of DB’s and CU’s. I think I’ve seen a couple of them with flyleads between case and cover but they might have been purpose built panels for machines and plant equipment.

Yes I hadn't considered that - Fusebox CUs do come with a flylead to the front case - but I've not seen it on other ones I've installed recently - and some of them don't have the best screw fixings *cough* BG and MK *cough* in my experience.

Though most CUs are coated steel, so I've never actually checked whether they are normally conductive when in good condition

 

[telectrix]

the reasons i would give it a C3 is that it does not comply with MI ( as westie pointed out), and if the screws were removed for decorating or whatever, a fault on the switch would not trip MCB. therefore it "is improvement recommended. ", because i say so (smiley).

 

[Dartlec]

Class 1 exposed conductive parts require earthing, if it’s earthed In situ then it’s no code.
best practice is to earth the plate directly however i dont see the issue if it’s earthed full stop by one way or another.
The regulations will not tell you how to earth it other than it requires earthing.

The instructions with the accessory will demonstrate a cpc to the front plate.

Very interesting discussion, and I can probably see the validity of every view. Thats the 'joy' of doing EICRs to a consistent standard.

My concern would be the worry that screws might come loose or a lug break with constant use of the switch (something that doesn't happen with CUs so much).

but if an R2 to the front plate is satisfactory, then it is probably acceptable to consider that effectively earthed without necessarily needing to remove it to check the earthing connection....

However, if I remove a front plate and find the earth not to the plate, personally I'd still feel duty bound to correct it there and then to avoid any further thought.

 

[westward10]

If I am in a domestic situation and there are metal light switches I always check them, it will be 50/50 if they have a cpc to them.

 

[Ian1981]

All earth wires must be terminated to the back box.
An example that not all MF’s instructions are the be all and end all.
Pick shows the cpc from the cable not directly to the switch.
This does however highlight that a fly lead is required

 

[Ian1981]

the reasons i would give it a C3 is that it does not comply with MI ( as westie pointed out), and if the screws were removed for decorating or whatever, a fault on the switch would not trip MCB. therefore it "is improvement recommended. ", because i say so (smiley).

I’d be more concerned with the exposed conductive parts exposed by removing the switch personally.

 

[Pete999]

All earth wires must be terminated to the back box.
An example that not all MF’s instructions are the be all and end all.
Pick shows the cpc from the cable not directly to the switch.
This does however highlight that a fly lead is required

It;s a M/C switch, terminate the cpcs into the back box and run a fly lead to the plate switch, how much would that cost you? not much I imagine then no need to code

 

[Midwest]

My two pennyworth; I've always terminated cpc into back box, then a fly lead to faceplate. My thinking is if cpc become disconnected when plate is removed and/or replaced, is just that particular plate, not the rest of that circuit. I've even taken it further with multi gang switches, and put all cpc's in wago, then flylead to back box and plate, for the same reason, and also you can't successfully terminate multiple cpc's into one back box terminal.