I am having a problem with double light switch in my kitchen...and would appreciate any advice before I call out an electrician.
In the kitchen I have a double switch (in a single gang faceplate) that separately operates a ceiling light and a set of under cupboard lights. The kitchen was rewired by an electrician about 6 years ago when we had a kitchen fitted.
For a while this one switch has been playing up - depending on how hard/fast you switched off the under cupboard lights would either blow the lighting circuit fuse (5A) or possibly trip the whole house circuit - I say possibly because I have recently fitted a plug in trip fuse for the consumer unit (just on this lighting circuit) to avoid having to fit a new 5A fuse in the dark each time the fuse went - and now the house earth leakage circuit breaker trips out as well.
This week the switch has started tripping the electric almost every time it is used. There is some soot/ burning to the inside of the undercupboard switch.
The new fuse/trip device in the consumer unit is the only change.Thsi repalced the old style 5Amp fuse holder at the consumer unit with a new plug in trip type which was at 6A (Wylex to match consumer unit). This was to avoid having to replace the fuse which used to go in the lighting circuit when the undercupboard lights
On inspection of the switch wiring there are two cables entering the switch backplate - both earths are connected to the metal back box. On the switch for ceiling light cavle ones red and black wire are connected to switch one COM and L1. There is a jumper wire from this switch L1 to switch 2 L1. The 2nd incoming mains cable has the neutral cable taped up (not connected) and the red cable enters switch 2 COM.
There is a junction box above the kitchen cupboard that the electrican has used to extend the old switch cable to the current position. On inspection the two switch cables (from switch back box) go to this junction box and connect separately to two further cables that go to the ceiling (upstairs floor ) - connections in this junction box are cable1 neutral to neutral / cable 1 live to live ; and cable2 neutral to neutral and cable2 live to live. Earths are all connected together. This junction box looks to do no more than extend the switch cable run,
The cable to the ceiling light is just that - a junction box / ceiling rose is not visible. When the kitchen was rewired the electrians had the floor in the bedroom above the kitchen up so I presume any junctions boxes are under the floorboards...and I haven't considered removing the carpet / floorboards yet to look for them. .
I guess my questions are ... - Does the cabling sound right (jumper etc from switch 1 to switch 2) - Any ideas what would cause it to trip ...(this happens even if all the undercupoard lights are turned off (they each have a built in switch). - Should I go back to the old style cartidge fuse ?
The trip unit on my house wiring is an earth leakage circuit breaker (my earth comes from a ground rod) .
Many thanks... Nick