Replacement low energy lamps fail to work

[Manyanga]

Can anyone explain what might cause low energy lamps to fail to light up when they are used as straight replacements for tungsten bulbs which were working fine? These lights are on the lighting cuircuit, not plugged in to the ring main. None are controlled by dimmer switches.

This is in an older two-bed terraced house that my daughter has rented. Some lamps work, some are intermittent, some fail to light up at all. All the lights in the house are on a single circuit with a rewirable fuse. I know fluorescents pack in sophisticated circuitry - could the problem be due to voltage drop? I have Megger test equipment, but I would rather see the buck passed to the landlord, if anyone can suggest a diagnosis.

 

[breezer]

the halogens , were they 12v?

 

[big-all]

i had a simmilar problem i am fully l/e bulbs
3 off my low energy bulbs failed to work properly over a 2 day period all others where fine
some of the replacments didnt work either
also notice the grill was taking ages longer to work!!!!

next day the juction box in the street caught fire shooting flames into the air
problem repaired and all the bulbs worked normaly again

 

[Manyanga]

None of the lamps are low voltage halogens - just standard Philips 240V Softones, 12W and 20W.

 

[breezer]

have you tried the lamps in say a bedside light to see do they work?

 

[Manyanga]

Yes, the lamps seem fine and work off the ring main. I have lamps from the same batch here at home, where we are almost all-fluorescent.

 

[Manyanga]

No pressure Breezer - but can I just add that though I'm posting for the first time, I have drawn for years on the advice that you and other regular contributors like Banallsheds give in this forum - it's my bible. So I know you guys must be able to come up with a reason ..............

 

[Softus]

Do you have a multimeter and insulated probes with which you can carefully measure the voltage at the light outlet?

 

[plugwash]

I would say the first thing to do in a suitation like this is to inspect and tighten every connection on the circuit.

 

[Manyanga]

Yes, I have the gear (and care!) to do that the next time I visit the place - it is 40 miles from where I live.

If you think voltage could make the difference between tungstens and fluorescents, meaning one could work and the other not, then I might suggest the landlord/letting agency is called on to deal with it. I guess any mention of faulty electrics will oblige them to test the system. I'm not sure what letting requirements are these days, but looking in the fuse box I doubt that the wiring would pass much scrutiny.

 

[Softus]

If you think voltage could make the difference between tungstens and fluorescents, meaning one could work and the other not...

Not only voltage, but also, as correctly implied by plugwash, the sum of resistances at all termination points.

...then I might suggest the landlord/letting agency is called on to deal with it. I guess any mention of faulty electrics will oblige them to test the system.

Not really - they could just find and then fix the fault.

I'm not sure what letting requirements are these days, but looking in the fuse box I doubt that the wiring would pass much scrutiny.

There is still no mandatory test, periodic or otherwise - it's just 'best practise'. However, the installation is required to be safe, and if it isn't then the landlord is liable for what happens subsequently.

 

[Manyanga]

Thanks Plugwash, you're right. But if there are loose connections, why would tungstens work and the le bulbs not?

I think I am looking for a reason to bring in the landlord to get the place checked independently. If there is a problem in the lighting circuit, I'd half expect problems elsewhere. I'll certainly check the quality of the earth loop when I'm next there.

 

[Manyanga]

Softus, would higher resistance in the circuit explain why LEs, specifically, might not work?

I have to say I am hoping I don't have to read up how the electronics in an LE bulb operate!

 

[JohnD]

low energy lamps are very tolerant of voltage fluctuations.

Are we talking about ordinary bayonet/ES lamps here? some low enery sticks do not contain their own electronic starters as they are meant to be installed in special fittings which contain the circuitry

have you tried the old lamps in different fittings, and have you tried ordinary filament bulbs in the fittings that don't work? If so, can you change the bulbholders? Might be that they are worn and not pressing the lamp bases into place adequately.

If they are ES screw-ins, there is a slight difference in size between UK and US screws so they might not fit right.

 

[tim west]

If they are ES screw-ins, there is a slight difference in size between UK and US screws so they might not fit right.

I would hope so as it might be a bit nasty screwing a 120v rated lamp into 230v