Burned wire behind cooker switch

biko

The cooker switch gave up the ghost and I unscrewed the facia.
As you can see the brown wire is pretty bad, can I just wrap it in electrical tape?
https://i.postimg.cc/bJYptCYw/IMG-20181215-150811.jpg
https://i.postimg.cc/R0kbrqy5/IMG-20181215-150837.jpg

Turbohymac

I not an electrician but it's fairly obvious..you will need to pull a few inches of that cable down to where it connects to the switch and cut off the damage cable and insulation..otherwise you will simply be connecting a new switch to old burned wire which will not connect/conduct properly to the switch..thus more problems..it looks like the connections on the old switch might have been loose and arcing over time caused your problem..

Bruthal

It looks like the damaged cable is the one down to the cooker.

It should be possible to pull up a little. The damaged part needs to be cut off, probably plus an inch or so more than the visibly burnt part. Then properly re-terminated.

The switch will probably need to be replaced also.

A loose termination looks likely to be the cause.

biko

Thanks guys, sorted it today. Cut away the brown burned bit and fortunately there was enough wire left to connect properly.

Steve

FYI, this is a classic loose connection. Also symptoms on the neutral on the LH of the pic. You should also check this is tight.

biko

I replace the facia and did all connections hand tight, didn't want to squash the wires, only make sure they are affixed properly.

I will check them again before Christmas, just to make sure it all looks good.
I'd rather check a few times than worrying about it

2011

biko wrote: »

I replace the facia and did all connections hand tight, didn't want to squash the wires, only make sure they are affixed properly.

I don’t know exactly what you mean but it sounds like you are not tightening the terminations sufficiently. It looks like the cable is a 2.5 mm sq. cable so don’t be worrying about squashing the cable. If you overtighten it is much more likely that the brass terminal screw cable will fail before the conductor is damaged. The heat generated is a function of the resistance, so a loose connection is bad news as it can cause high resistance.

Heat generated = (current^2) x resistance

Each conductor should be doubled over and the termination should be tight, end of.

Steve

What 2011 said.

You need to 'squash' the conductor slightly to get a good electrical connection. It will increase the surface are in contact with the terminal.

About 1/2 to 3/4 turn past where you feel it first bight.