How do you do your Earth?

[kevindgas]

you are correct not all have them but the ones that do should be wired as i said 1 leg of ring to each tag the bar between them becomes part of the ring.



cable infrom last socket or CU /tag/ bar across/tag/ cable out to next socket or back to CU

 

[GaryMo]

Two earth terminals are primarily for circuits that require high integrity earthing.

Under normal circumstances there's nothing wrong with putting both CPC's in a single terminal and the flying lead to the backbox connected to the second terminal. There's certainly no 'should be' about it.

I was confused with you mentioning creating a ring through the switches, almost as if you expected the switch to isolate the connection between the two earth terminals. Obviously it was a typo.

 

[mikhailfaradayski]

if your not sure, earth it.

However, if there is one fixed lug on the back box there is no need to add an additional wire from a metal face to the back box, if using metal screws.

You would also have to be certain that continuity would exist (corrosion etc) between the screw and backbox throughout it's usable life.

I've always fitted links, see it as good practice and will continue to do so.

If proper materials were used in an evironment that suits their use and good workmanship has been employed, then the continuity will exist between the screw and B/B. Another thought is when the switch plate is fixed correctly into position, the back box is not an exposed conductive part, why does it need an earth?

As i said before, if you're not sure, earth it, but i would be interested to see if anyone can find a reg that says the back box needs to be earthed. I bet 1 english pound it can't be shown.

As mentioned before, the socket outlets with 2 e terminals are mainly for use on circuits with expected high leakage currents. Not required under general circumstances.