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[ian00uk]

a friend of mine has a problem in his house. in room 1 there is a ceiling rose with a 1 way switch. In room 2 there is a ceiling rose with a dimmer switch. when you use the dimmer switch in room 2 to make it brighter, the light in room 1 dims lower and vice verser. when the light is off in room 2 the light in room 1 is on but if you were to turn room 2 light on with the dimmer the light in room 1 will go off.

im thinking its a faulty dimmer switch as its quite noisy and looks like its seen better days.

any help would be great

thanks

[ericmark]

More likely that the neutral and switch return wires have been swapped. In the ceiling rose.

[ian00uk]

so how can you find out which black is the switch return when there is 3 blacks and cant get into loft to follow the cables

thanks

[ericmark]

I have tried many times to give a system of using the lamp it's self as a test lamp and worked out how to work out the correct wire.

However it seems people get into real knots trying to follow the method.

There are of course only three options. However one will produce a short circuit when power is switched on.

So lets look at options.

1) The black going to pendent at moment is not the switch wire or it would work OK.
2) If the neutral was connected correctly then when switched on the fuse/MCB would blow.

So the wire going to the pendent must be real neutral.

If you remove both wires in neutral block and replace it with wire at moment in pendent line block and connect one of the wires that was in neutral you will get one of two scenarios.

1) First light works A1 and other light does not work. In which case you have connected the switch wire to pendent and all that remains is to connect remaining wire to neutral.

2) First light only works when second light is switched on and half on only. In which case the wrong wire has been connected to pendent and one in pendent now should go to neutral block and disconnected wire should go to pendent.

Just logic. However each time I have tried to explain this it seems mistakes are made. If you read the "multimeter" post you will see how some one else is trying to correct the same problem.

However carefully any of us try to explain it seems there are always mistakes and really once one has lost the marker it is a call in an electrician job. Not only is there a problem getting the right wire in right place but it seems that people also forget to turn off the mains each time and there have been so many times where people have for some reason ended up with a belt I strongly recommend you get some one in to do the job.

[ian00uk]

sorted.

thanks for the help