Correct way to earth - shaver socket and light switch

[patrick187]

I have two questions but because they are both questions about earthing I thought I would only post once.

1) I replaced a broken plastic (face plate) shaver socket with a metalic one . I disconnected the old socket and wired the new one the same way. The unit works fine but I wanted to check that I have earthed correctly (see photo). The earth cable coming from the top and the bottom are clamped together into the unit. Is this correct or should both cables be conected to the same connector on the mounting box and a third yellow and green cable go to the connector on the unit?

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• patrick187
• 20 Mar 2011
• 1

2) I replaced a switch with a remote control dimmer switch (Varilight) with metal plate behind the plastic. I wired in the same way but I have not got the unit earthed. Like with the shaver socket there is a earth (yellow and green) cable coming from above and below and they are both connected to the metallic mounting box. Should a third cable be connected from this to the switch?

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• patrick187
• 20 Mar 2011
• 1

In respect of 1) and 2) alternatively should I just connect to the existing earth cables as per the following diagram and not try to connect the metallic mounting box as well? This is essentially what I have done with the shaver unit.

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• patrick187
• 20 Mar 2011
• 1

Apologies in advance for what may prove to be some very stupid questions but I would rather ask than get electrocuted! BTW the property is a 3 year old conversion from offices to flats and must have been re-wired then.

 

[holmslaw]

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[Adam_151]

If your recessed boxes have at least one solid mounting lug in a recessed mounting box, then its allowed for them to be earthed from the front plate screwed back onto it (but not vice versa, i.e. the earth path to the bit on the front must not rely on the screws), but good practice to fit flylead, but done less and less these days

Holmslaw, whats wrong (other than not being the best practice) for a socket to have the earths in the twins to the backbox lug and then a flylead to the front... I wouldn't do it, but I wouldn't feel the need to alter it either!

 

[holmslaw]

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[Adam_151]

It is also very wrong to advise that flyleads are not required and that plate fixings screws make an adequate earth path.

Its the official line of the NICEIC, recessed flush mounting box with at least one fixed lug, then earths to the accessory and box earthed through the screws is acceptable, if this is very wrong then perhaps you ought to tell the NICEIC

That doesn't affect that its still good practice to fit the link though (though dingbat will try to tell you that you are wasting your time completely!)

I have on snagging of jobs picked up on a certain manufacturers flex outlet plates which didn't have the earthed eyelet holes around the screws, and surface metal clad boxes, without links fitted and required that links get fitted. Its true that if there was an automatic thing for people to fit links whereever, then these would have never arisen in the first place

And it is not true that it is 'done less and less these days' I have never worked for any company that did'nt specify the need for flyleads.

I suggest you have a look behind a socket in any domestic property built within the last 15 years, chances are that flyleads wont have been fitted, likewise with 16mm light switch boxes with two fixing screws, noggins behind every pendant set, and holes through rows of joists drilled with a chalk line

 

[holmslaw]

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[Buzx1313]

only time you should always use a fly lead is with surface mounted metal boxes.. ie when carying out a conduit installation..