Changing ligt switches.

[happyhacker]

I have noticed when doing this and needing to add an earth wire to the plate (metal) that the earth wires coming in are very dirty and am having to clean them. I assume the rest of the system may have "dirty wires". What's the best way of testing if there are any faults?

 

[Sintra]

By dirty do you mean dull?

 

[oldtimer]

When you strip cable either T+E or single core you get a nice gleaming copper cable but leave it esposed for a while and it starts to oxidise or in other words protect itself if its indoors then it goes dull outdoors it goes green. As for dirty wires me thinks it does not have a big impact on testing

 

[telectrix]

I have noticed when doing this and needing to add an earth wire to the plate (metal) that the earth wires coming in are very dirty and am having to clean them. I assume the rest of the system may have "dirty wires". What's the best way of testing if there are any faults?

if they're tagged onto a metal back box, the most likely cause will be a bit of damp in the walls

 

[SirKit Breaker]

I have noticed when doing this and needing to add an earth wire to the plate (metal) that the earth wires coming in are very dirty and am having to clean them. I assume the rest of the system may have "dirty wires". What's the best way of testing if there are any faults?

Continuity test, followed by an Insulation resistance test.

Cheers..........Howard

 

[happyhacker]

Well, when I have need to change the switch I will scrape them clean. I have put a pluin tester on the power sockets and that's showing all OK.