Damaged earth connection in backbox. What do I do?

[veedee]

Many thanks for the help guys. All sorted now

 

[pete50]

Does the metal front plate of the socket have an Earth Terminal that is separate to the Earth terminal for the socket Earth, ?

If it does then these need to be linked together to ensure the metal front plate is securely Earthed in the absence of a secure Earth to the back box.

Also do as Harry has suggested but a self tapping screw should not be relied upon to prove a secure Earth connection.

I would have thought that a self tapping screw would be a far far better connection than those stupid riveted things that invariably pull away.

 

[Risteard]

Better to try to squeeze all the cables into one terminal, rather than rely on the socket's linking of one earth terminal to the other.

I disagree. Better to put one of the ring final circuit conductors into one and the other into the other. This leaves it ready for high integrity Earthing (e.g. for high protective conductor currents) leaving only the DB to be arranged this way also.

 

[Harry Bloomfield]

I disagree. Better to put one of the ring final circuit conductors into one and the other into the other. This leaves it ready for high integrity Earthing (e.g. for high protective conductor currents) leaving only the DB to be arranged this way also.

The fewer the number of terminals and riveted links the earth as to pass through, the better and the safer if one of those terminals or links goes o/c or high resistance. I wasn't suggesting forcing them into one terminal, rather I was suggesting if it was practical to do so.

 

[Risteard]

The fewer the number of terminals and riveted links the earth as to pass through, the better and the safer if one of those terminals or links goes o/c or high resistance. I wasn't suggesting forcing them into one terminal, rather I was suggesting if it was practical to do so.

You're missing the point. Instead of a single failure causing the entire connection to be lost it will reduce the cross-sectional area but leave a path in place.

 

[winston1]

Many thanks..

I had a peek on youtube and it appears that this is quite a contentious topic in the sparky community

Lots of rubbish posted on youtube. Taylortwocities is right.

 

[SUNRAY]

I have not seen a BS1363 socket that has anything other than this arrangement.

Oh yes! we have often fitted them in audio visual rooms, the backboxes/frontplates are connected to the normal earth but the earth pin of the socket [and all of the AV kit] is connected to a separate 'clean earth'. It's usually run as a thick cable directly from the main earth bar to a local earth bar and distributed around the AV system from there.

EDIT: note to self to read more before replying, I didn't see Bernards reply onwards.

 

[DIYWell]

Taylortwocities is correct according to the testing regs.

AV folk like clean earth because they fear feedback from earth loop induction.

13A sockets which use T shaped earth pins in their plugs require a separate clean earth. The metal back box is connected to CPC. If you find one in a house, it will invariably have medical equipment plugged in e.g. dialysis machine. This protects the patient from earth faults in the house.

 

[SimonH2]

You're missing the point. Instead of a single failure causing the entire connection to be lost it will reduce the cross-sectional area but leave a path in place.

And what's more, you stand a good chance of it showing up during testing.
With some installation techniques, you stand a chance of losing the CPC to one item but stll have ring continuity.