New earth

[zafs1987]

Hi im replacing some sockets and switches. Ive replaced the brass ones and managed fine. I had noticed they back boxes werent earthed so connected earth from the faceplate to back box. Also some werent sleeved so managed to sleeve these.

Only problem is that some are plastic and have no earth. Im putting chrome paltes with plastic switches. these have no earth connection. How do i earth these. Maybe a noob qiestion but the cable has three wires in. Two connected and one naked copper on which is cut short. Is it safe to assume this is the earth.

Sorry if silly question.


Zaf

 

[EFLImpudence]

Hi im replacing some sockets and switches. Ive replaced the brass ones and managed fine. I had noticed they back boxes werent earthed so connected earth from the faceplate to back box. Also some werent sleeved so managed to sleeve these.

All good.

Only problem is that some are plastic and have no earth.

Just terminate it in a connector block and position safely.

Im putting chrome paltes with plastic switches. these have no earth connection.

Are you sure. Chrome plates certainly should.

How do i earth these.

Don't know yet. Can we have a picture?

Maybe a noob qiestion but the cable has three wires in. Two connected and one naked copper on which is cut short. Is it safe to assume this is the earth.

The bare conductor is the Circuit Protective Conductor (CPC - earth wire)
It should be connected to earth at the other end but you never know.

It should never be cut as it may be needed one day, as you have found.

 

[zafs1987]

Im putting chrome paltes with plastic switches. these have no earth connection.

Are you sure. Chrome plates certainly should.

Sorry what i meant was there is no earth connected to the current plastic one. There is on the chrome one.

How can i check to make sure the cpcis connected to earth?

 

[EFLImpudence]

You will need multimeter set to low ohms (&#937.

Power off at the main switch - test for dead.

One probe to the CPC of the cable at the switch.
The other probe to a long wire.

The other end of the long wire to a known earth.
This can be, ideally, an earth block (rectangular metal block with several green and yellow wires connected) near your consumer unit if there is one.
If there isn't one then to a socket screw, if the back box is metal, or an earthed metal appliance - e.g. oven or hob.

The reading should be a few ohms or a 'beep' from the multimeter

 

[Steve]

Sometimes (quite often) you will get continuity between neutral and earth, to verify for continuity on the CPC. But you won't usually have a neutral at the light switch! (You may have a black/blue wire but it wont be a neutral if its connected to the switch)

 

[EFLImpudence]

Sometimes (quite often) you will get continuity between neutral and earth,

Not if the main switch is open.

 

[Steve]

True it only works if you have isolated just the one circuit using its mcb.