DIY Doctor UK DIY Forums

hello all, i hope you can help.

i am trying to fit a new light fitting which is basically a block of 3 halogen lights. the light fitting has therefore 3 neutral and 3 live + 1 earth together with a white connector block. the 3 neutral are all tied into 1 terminal in the block, same with the 3 live, and earth goes into 1. there is a spare empty 4th terminal in the block.

i want to replace our old light in the hall. the hall has 2 independent switches that can operate this 1 light.

i took apart the ceiling rose and took all the wires out. there appears to be 3 pairs of live/neutral sheathed in white, + 1 independent earth.

i notice that with all these wires dangling out of the ceiling that no lighting occurs in the kitchen.

I thought to myself that it would be easy, and so I twisted all 3 lives and all 3 neutrals and matched them into the connector block of the light fitting.

when i put the mains back on the light worked without any of the wall switches being on.

i pressed a wall switch to see if it turned it off but doing that seemed to blow a fuse, the light went off and the switch on the wall did not work any longer (i.e. the spring seems to not click up or down - i guess the fuse in there is gone).

i disconnected that switch and the light overhead worked again. i then used the other wall switch - same thing happened, it's blown.

i understand only slightly the concept of a loop-in. i don't know how to work out which is the switch wire, and i don't know how to link all these wires in the ceiling to the light fitting i have .. i can't use the traditional loop in type connector block as all i have is a white connector block with 4 terminals.

i do have a dc reader if this will help me but when i used it, it only showed me which red/black combo was live .. is that the black switch? do i need to route the switch cable into the 4th empty terminal on the light fitting connector block?

hope this is enough info. i'd rather attempt this myself if possible.

Some of the black wires are not neutral. Theyre live returns from switches. What youre doing is such a cliche. Youre connecting black (or blue) live wires to the neutral. If you put a circuit tester on some of these cables, you'll find that there is a short circuit across live and neutral when the switch is on. they are the ones that shouldnt be connected to neutral. If you saw new expensive houses, theyve taken the trouble to use cable with two red wires and earth. This isnt the case mostly. Work out which are the switch wires. These will be live whatever colour they are, or get an electrician in

See our project on lights and switches under the electrical projects. All of the information you need is in the projects section as advised at the top of every post.