Shock from screws on light switch

[onion50]

Thanks , As far as I know it was just a replacement fitting, cannot see any new wiring. I am currently doing an electrical installation course and was ask to have a look. So I just had a look for the obvious ....Loose connections, damaged insulation ect. Have isolated supply & told him to get an electrician. Thanks.

 

[onion50]

my mistake didnt read all opening post, sounds like that should be isolated at board, must have screwed through cable.


there are really only two options if the cable has been screwed though.

make a mess of the ceiling and patch it or.

attempt to find damage by lifting boards above then reassess the situation

Cannot lift boards is flat roof extension . Why would it make the metal back box live with no connections to it ?

 

[shanky887614]

Cannot lift boards is flat roof extension . Why would it make the metal back box live with no connections to it ?

live shorted to earth

 

[davesparks]

This is unfortunately a familiar situation, I've come across it a couple of times.
The cpc is either not connected or not present somewhere in the circuit before it gets to the affected switch.
This will work perfectly well whilst no other fault is present.
Now a short has occurred between the live and the core which would normally be connected to earth, and since this is connected to all the metal parts of the circuit they all become live relative to earth.

 

[davesparks]

Thanks , As far as I know it was just a replacement fitting, cannot see any new wiring. I am currently doing an electrical installation course and was ask to have a look. So I just had a look for the obvious ....Loose connections, damaged insulation ect. Have isolated supply & told him to get an electrician. Thanks.

What electrical installation course are you doing?

 

[Knobhead]

Cannot lift boards is flat roof extension . Why would it make the metal back box live with no connections to it ?

Are you a qualified electrician? Have you any experience in fault finding?

Get someone who knows what they are doing.

 

[davesparks]

Tony, he's already said he is in training. I've asked what course he's doing but am yet to get a reply. I'm sure you can guess what I am expecting the reply to be!

 

[happysteve]

He's also said (post #16), "Have isolated supply & told him to get an electrician. Thanks."

 

[onion50]

What electrical installation course are you doing?[/QUOTE

At present C&G 2365 then 2357. Have enrolled in a distance learning course. Not ideal I know & frowned upon by some Sparkys, & for good reason. But at 49 & in full time work only way I could have a career change.
Thanks for the advice.

 

[Silly Sausage]

Are you a qualified electrician? Have you any experience in fault finding?

Get someone who knows what they are doing.

On occasions like this, it's best just to walk away and say nowt!

 

[Knobhead]

Are you a qualified electrician? Have you any experience in fault finding?

Get someone who knows what they are doing.

I’ll reiterate the above point "Get someone who knows what they are doing." I'll add, don't touch that you clearly don't understand.

 

[Knobhead]

On occasions like this, it's best just to walk away and say nowt!

Maybe your right, there’s plenty of Electrical Trainee’s to give him advice (wild guesses).

 

[onion50]

Grumpy Git .....NO, Yes & Yes ......Bet you're a bundle of laughs in the pub !
But Thanks anyway.

 

[davesparks]

What electrical installation course are you doing?[/QUOTE

At present C&G 2365 then 2357. Have enrolled in a distance learning course. Not ideal I know & frowned upon by some Sparkys, & for good reason. But at 49 & in full time work only way I could have a career change.
Thanks for the advice.

Then I was wrong in my assumptions and owe you an apology. You are clearly going down the right route and getting the proper qualifications.

Get in touch with a mod if you want access to the trainee forums, there'll be plenty of help there if you need it.