Problem replacing a pull string bathrom switch! Ask questions and find answers to many subjects relating to electrics and electrical work

[Psm1th]

Hi there

We tried to replace a pull string switch yestreday which seemed to be going fine until the very end of the process.

We removed the old pull string switch. The wiring for the switch is the old type of red, black and a bare earth. I wired up the new switch and turned the power on. I tested the light and it worked okay. We then turned the power off and finished screwing the new switch to the ceiling and put the plastic cover on. When we turned the power on again the lighting circuit fuse in the fuse box blew.

I replaced the fuse wire. When the power was turned on again only half of the lights in our flat will work now. I assume that something is not quire right in the lighting circuit. I have checked the wire cable to make sure i didn't screw into it when i did the final bit of attaching and it seems fine. I have tried re-wiring the new light in all ways I thought could be right and I still the same problem. I have tried attaching the old switch and still half the lights won't work.

Both the old and the new switch are common two way switches but we only have one light attached. There is a common pole and an L1 and L2 pole. Could anyone please confirm which wires should go where to make sure I have tried the right variation and what the possible problem might be which is causing the rest of the light problems?

Any help much appreciated.

Phil

[kbrownie]

Hi Phil.
Firstly the bare earth should be sleeved with green and yellow sleeving can be purchased at most electrical wholesalers and DIY shops.
Then Red Cable to Common and Black cable to L1 and earth to earth terminal.
You may have blown bulbs in other lights and that's why they don't work
KB

[Psm1th]

Hi KB

Thanks for the quick reply.

The way you described is how I wired up the new switch. Would all of the bulbs have blown? In total the number of bulbs not working is 12 and are spread amongst 4 different rooms and it is all of the lights in all of these 4 rooms which are not working.

[kbrownie]

Psm1th,
Does sound a bit unlikely, If the light worked before you screwed it up and the rest of the lights worked too, it sounds like you may have shorted it, you may have severed a cable in the ceiling or pulled a cable out of it's terminal when fitting light.
What cables are the switch and at the light fitting in the bathroom.
KB
Ps just added a bit more that should have put originally.

[stevenc1603]

Check the switch you were working on. Its possible that you have managed to screw into one of the wires and that caused it to short out and blow the fuse. It may even have blown with enough force to burn the wire away from the screw so that you now have half the circuit working and the other half not.

As you have only worked on the one switch, chances are its here the fault lies.