Two Bulbs With two Switches but Bulb Staying on
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Ruthers
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Two Bulbs With two Switches but Bulb Staying on

Post by Ruthers » Tue Jul 18, 2017 12:19 pm

Hi, I've just moved house and I am having trouble with the lighting in the garage.

One light works as it should on the switch (switch on, bulb on / switch off, bulb off). But one bulb remains on regardless of the position of the switch

Can anyone help me please?
I've attached images of both switches and both bulbs.
The bulb with the most wires is the one that functions correctly.

Thanks,
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kbrownie
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Re: Two Bulbs With two Switches but Bulb Staying on

Post by kbrownie » Tue Jul 18, 2017 8:18 pm

Looks like you have the switch live/line for the second light (the one staying on), in the permanent live loop on the first light fitting.

It will be one of the 4 browns in the middle section on the ceiling rose, it needs to be in the switch line terminal, with blue sleeved brown.

If you have a multi meter you could test it out, to establish which one it is, If no meter it is guesswork/trial and error. Swapping the browns about from live loop to the switch line terminal, will not blow anything, But do not go into the neutral terminals. It is much better to dead testing the conductors though.

Switches look fine, don't forget to safely isolate before touching.

ericmark
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Re: Two Bulbs With two Switches but Bulb Staying on

Post by ericmark » Tue Jul 18, 2017 10:06 pm

Problem is with ceiling rose with a lot of wires, in the centre you have 4 brown wires, it is likely one of those brown wires should go to the terminal with 2 brown wires.

Ruthers
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Re: Two Bulbs With two Switches but Bulb Staying on

Post by Ruthers » Wed Jul 19, 2017 6:43 pm

Thanks for both of your replies.

I've tested the cables coming in with a fluke multimeter on the continuity setting.

I first tested the cables together to prove the meter. That was fine.

I then tested the current switched live and neutral coming from that 3 core. That was fine.

I tested the rest of the cables coming through the ceiling and only one gave any indication of continuity. The beeping was intermittent, not continuous like the current switched live and the test cables together.

Wired it up as suggested. (Moved the new tested switched live to the switched live terminal with the current switched live).

This now results in:
•switch up - light number one on and light number two off
•switch down - light number one off and light number two on

I believe I'm further forward, but not just there yet.

Any guidance please?

Ruthers
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Re: Two Bulbs With two Switches but Bulb Staying on

Post by Ruthers » Wed Jul 19, 2017 9:28 pm

CORRECTION:

• Power reinstated to system by deisolating at consumer unit.
• Closest switch nearest consumer unit (which is in garage) in up posisition
• Bulb one fully illuminated. Bulb two completely off.
• Switch pressed down.
• Both bulbs now are glowing dim.
• Switch pushed up.
• Bulb one fully illuminated. Bulb two completely off.

So in summary, switch up: one on, one off.
Switch down. Both dimly lit.

Thanks again.

kbrownie
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Re: Two Bulbs With two Switches but Bulb Staying on

Post by kbrownie » Thu Jul 20, 2017 6:28 am

Isolate the circuit.
Remove all browns from the ceiling rose at Light one (the one with four browns)
Then at the second light, connect the earth and brown together.
Using your multi-meter, set it to low omhs continuity and test between earth and each brown at light one. The one that shows continuity, is the switch line brown. That goes with the blue that is sleeved brown at the switch line terminal.
All other browns back into the middle live loop.
Then reconnect the earth and brown as before to second light.

Ruthers
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Re: Two Bulbs With two Switches but Bulb Staying on

Post by Ruthers » Thu Jul 20, 2017 6:54 pm

Finally sorted it!
Both lamps work as they should now.

Thank you both very much for your help.

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