How do I determine......
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TheAbz
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How do I determine......

by TheAbz » Tue May 01, 2007 6:51 pm

which of the 3 black wires from the cables for my light fitting is the SWITCH LIVE.
I have 3 reds. 3 Earths and 3 blacks...of which i believe 2 should be neutral and one a switch live.
a step by step type intstruction guide would really be appreciated.
Thank you.

sparx
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by sparx » Wed May 02, 2007 8:50 pm

I wish i had a Quid for every time this one crops up....
You should have marked the black on it's own before disconnecting, presume changing light so three reds go to spare loop-in connector, not to fitting.
two blacks together go to neutral of fitting & remaining black, after marking as red with tape etc goes to fittings live connection.. earths together to fittings earth.
if disconnected and blacks not identified some times sw.line black will have been 'doubled over' or neutral blacks may have been twisted together before and you can tell by close inspection, (power off).
if still not sure, with circuit dead connect a meter on ohms range to the 3 reds together and the other wire to each black in turn whilst turning switch on/off/on untill meter responds to show the switch line black, mark it with red tape and see above.
if no meter avail. a battery/bulb/buzzer will do,
If still stumped Get Someone In.....best wishes SPARX

TheAbz
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Posts: 12
Joined: Sun Apr 29, 2007 9:04 pm

by TheAbz » Thu May 03, 2007 4:55 pm

Cheers Sparx...got me multimeter on it and found the switch live..all the lights work now but one of them seems to take its time coming on....but better late than never as the saying goes.
Much appreciated sparx.

P.S...a great service to have.

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