Kichen Spotlights keep blowing

Wavey

Evening all.

I'm living in a 30yr old house with all original wiring.

We had 2 sets of 3 spotlights in the kitchen wired back to one double switch. (1 switch for each set of three). The bulbs on these kept blowing untill there was one left out of the 6. The last one lasting for ages.

Thinking it was the spots them selves I replaced them today with 2 new sets of 4 each. That was 6 hours ago and one bulb has already gone.

Can anyone suggest what the problem might be?

I'm thinking i need to split the bulbs up so that I have one switch per 1 or 2 bulbs.
Would this make sense?

Any advice appreciated.

Wavey.

northdublin

when your fitting the bulb are you touching them with your hands. the oil from your fingers can sometimes cause the bulbs to blow when they heat up.
are they 12 volt or 240 volt. they 12 v usually have 2 pins also you might try replacing the traffo if they are 12 v

Wavey

Thanks for the reply Northdublin.

The bulbs are 240 volts.

And i used my bare hands putting them in.

Will use tissue when replacing this one and see if this is the problem.

Thx
Wavey.

10-10-20

GU10 bulbs do not suffer from this problem. 'Capsule' type bulbs do.
Which type are you using?

I'd be looking to measure the voltage at the outputs just to see whether you have transformer issues as northdublin said (12v only!). You need to measure it when loaded (bulb connected and live) otherwise the unloaded circuit voltage will be misleading.

cast_iron

10-10-20 wrote:

I'd be looking to measure the voltage at the outputs just to see whether you have transformer issues as northdublin said (12v only!). You need to measure it when loaded (bulb connected and live) otherwise the unloaded circuit voltage will be misleading.

Well the OP did say it was 240v, but in any case, I can't see how not having a load will mislead?

I'd check the voltage at the light fitting in any case. A higher than normal voltage could cause the bulbs to blow.

10-10-20

Sorry - I overlooked his last post.
12v transformers will output a higher voltage when unloaded due to the smooting capacitance. Once loaded, this drops away. 240v will not exhibit this.

twenty8

When I was building my house the builder asked me if I was putting spots in. The reason that he needed to know was that he had to make a larger space for the spots. Standard ceiling spaces tend to be too small and the heat builds up and blows the spots.

Not sure about a remedy though.

Stoner

10-10-20 wrote:

Sorry - I overlooked his last post.
12v transformers will output a higher voltage when unloaded due to the smooting capacitance. Once loaded, this drops away. 240v will not exhibit this.

Em the 240Vac transforms to 12Vac, are you sure there is "smoothing" taking place?

Stoner

10-10-20 wrote:

Sorry - I overlooked his last post.
12v transformers will output a higher voltage when unloaded due to the smooting capacitance. Once loaded, this drops away. 240v will not exhibit this.

Em the 240Vac transforms to 12Vac, are you sure there is "smoothing" taking place?

10-10-20

Em, I cracked open a step-down transformer that I have here, and guess what I found - no smoothing cap. I could have swore blind that I saw one in a lighting traffo recently, but it may have been PFC or noise related. Sorry to create noise like that...

Mellor

twenty8 wrote:

When I was building my house the builder asked me if I was putting spots in. The reason that he needed to know was that he had to make a larger space for the spots. Standard ceiling spaces tend to be too small and the heat builds up and blows the spots.

Not sure about a remedy though.

Where exactly were your spots going.
I can see this being an issue in some areas of the house, but not in the kitchen.

Stoner

Wavey,

Just as a matter interest where are you getting your new lamps, are they a known make , or are they those unbranded ones carried by Euro Value Shops and the like?

So your spots are surface mounted not recessed, and are 240Vac so there is no issue with heat on a traffo or a recessed lamp.

The only things I can think of are
1. bad connections in some B&Q light fitting
2. bad batch/poor quality lamps.
3. some sort of supply voltage issue (least likely option IMO)

Like the others said, I'd check the supply voltage anything between 220 and 240 V should not be an issue for these lamps.

Wavey

Thx for all the advice lads,

no bulb has blown since so i hope it was juts the old spots.

Wavey

dingding

Ususlly where bulbs blow, it can be,

Heat not escaping, fillament overheating and bulb blowing.

Cheap, low quality bulbs.

Also just be careful as a previous poster said, if the spots were fitted after the house was built there could be a problem with heat building up in the cealing void which could be a fire risk.

In my house I noticed one of these was put in next to a cealing joist and the joist had turned black and had started to smoulder.

You should try replacing the bulbs with LED or Flouresecnt bulbs, you cna get both types that work with 220-240 volts and the fittings that you have. Or at a minimum make sure you use 35 watt instead of 50 watt bulbs.

You could also put in different fittings where the bulbs are not in the roof space.

http://www.lamps2udirect.com/pixs/front/28.jpg


These will not suffer from heat problems and should not blow.

richie_rvf

I have had endless trouble with bulbs blowing through out my house, almost one a week! Apparently it is due to the fact that I am first on a spur from the main line

Anyway, the solution we had was to replace every bulb in the house with energy savers (Phillips), that was between 2 and 3 years ago now and I have NEVER replaced a bulb since.

Worth a try,

Richie.