Ceiling light help.

[cookiecat]

Hi, My husband has changed 5 light fittings at his mums house today from chandelier type lights to ordinary ceiling pendant lights, all of them were wired the same, 3 wires coming from the ceiling (black, red and yellow/green) which he wired into the ceiling rose and everything worked fine ...but one of the lights is staying on even when the light switch is off, it is wired exactly the same way as the other 4 lights and the 3 wires from the ceiling all look identical to the ones in the other light fittings...any ideas on how to fix this?

he refitted the old chandelier type light fitting and it works fine, have also tried different ceiling roses and they also stay on when the light switch is turned off...

the ceiling rose is a standard 250v.

 

[PrenticeBoyofDerry]

you say three wires. So is there only one red, one black and one green/yellow cable at each fitting? If so would be very difficult to get it wrong.

 

[cookiecat]

yes just 3 wires, thats why we cannot understand whats wrong, all the other light fittings work fine but no matter what rose is attached this one light stays on all the time, although it is dimmer when the light switch is in the off position....but it doesnt stay on when the chandelier is fitted.

 

[PrenticeBoyofDerry]

Is the new lamp suitable for being dimmed? I would first test the light by replacing dimmer with standard rocker switch, this will rule out certain aspects of the reasons behind the fault.

 

[cookiecat]

Is the new lamp suitable for being dimmed? I would first test the light by replacing dimmer with standard rocker switch, this will rule out certain aspects of the reasons behind the fault.

it isnt a dimmer light, it is just that the light is dimmer when the light switch is in the off position and brighter in the on position...but it is on all the time. Its just a standard ceiling rose with a standard switch.

 

[PrenticeBoyofDerry]

Does not make sense, if you only have three cores at the ceiling, have any of the switches been tampered with?
Could you upload some pictures?

 

[cookiecat]

cant get any photos tonight as the lights were fitted at my mother in laws and we are home now but i will get some next time we are there...as far as we know the switches havent been tampered with but we cant be sure, what should have been a 10 minute job took over 3 hours today and it still didnt get done...why would a standard ceiling rose stay on all the time and a chandelier typr fitting not??
its very confusing.

 

[PrenticeBoyofDerry]

I can only see that fault arising if there where other cables at fittings that are part of the supply loop. But if only the three cores at each fitting and the switches have not been touched, does not seem logically, unless by chance the switch has developed a fault, could be worth swapping this one over for identical type and see if the problem continues or is relocated with switch.

 

[cookiecat]

the chandelier type fitting was a AC 50 hz 220-240 v
the new pendants are marbo excel 250v (standard ceiling rose)

all 5 chandelier type light fittings were changed to exactly the same type of pendant lights, all 5 were wired the same way, just this one light that we cannot get sorted, even trying different roses didnt help, my husband has just mentioned that the light is in the same room as the fuse box, which is the living room, not sure why this would have any effects though and still confused as to why the chadelier light swiches on and off perfectly but the pendant light stays on.

 

[PrenticeBoyofDerry]

You indicated in your first post that you had also tried changing this fitting for another and the fault was still present. So that should rule out a faulty fitting, three cores only would suggest you could not possibly loop perm and switch live, so my assumptions would say look at the switch, it could be that the mechanism is damaged and although it my seem to be operating between on/off, it is not releasing the switch contacts.

 

[sparkwright]

Are certain it's three wires?

Are you sure it's not three CABLES, each cable containing three WIRES?

If so, this would certainly suggest he's wired something wrong.

 

[cookiecat]

Are certain it's three wires?

Are you sure it's not three CABLES, each cable containing three WIRES?

If so, this would certainly suggest he's wired something wrong.

there is just one cable containing 3 wires, one red, one black and one green/yellow, just as there was with all the other fittings changed today...husband had his hand in the ceiling trying to feel if there was anything else up there but there didnt seem to be.

 

[sparkwright]

Has he worked on any of the light switches?

 

[cookiecat]

no, we assumed that because the old light fitting worked properly that there wasnt a problem with the switch that it was somehow something to do with the wiring or fitting but we ruled out the fitting after trying different ones...but it sounds like we might be wrong

why would the switch work properly on one light fitting but not the new one?

 

[PrenticeBoyofDerry]

Like I said, by the information given you have a faulty switch!