Halogen bulbs blowing

[pappyon]

I recently fitted 2 new 240w kitchen lights which have 3 of 50w GU10 Halogen bulbs fitted in each one.

One of these lights has already burnt out 2 bulbs yet the lights have hardly been on for five minutes in total since being installed, as we aren't even living in the house.

The bulb that has blown is in the same light fitting and it's in the same bulbholder. Does this mean there is a fault in the light or is it just a coincidence.

Surely if it was a fault in the light, all the bulbs would blow, or the light wouldn't work at all

 

[chivers67]

firstly what make are the bulbs you've used?

 

[pappyon]

They are called Arrow bulbs.

I bought them on the internet.

www.yourwelcome.co.uk/

 

[wingcoax]

Even the "5 YEAR" bulbs (sorry lamps) dont seem to last very long, as i have found out. Now i don't fit them and advise customers not to buy them.

 

[ericmark]

Quartz Halogen lamps are very dependent on correct voltage to work correctly both under and over voltage will shorten their life. In areas where the voltage is stable the GU10 works well but where the voltage fluctuates then some form of stabilisation is required. The extra low voltage versions are often supplied by switch mode inverters rather than transformers which help to stabilise the voltage. Also the thicker element works better so in all the lamps last a lot longer.

However the extra low voltage models can't work with compact fluorescent lamps and as yet the LED lamps are not really bright enough. So with the withdraw of lamps giving less than 40 lumens per watt the extra low voltage type have a limited life likely 2012 unless some other lamp is developed.

Also at the moment the compact fluorescent lamps tend to be longer than the tungsten types and will not fit in some of the lamp holders.

It seems however there is nothing to stop shops selling items which will be soon obsolete and many people are still buying fittings which will be of little use after 2012 and even earlier in some cases.

It is possible that spot lights will be made exempt and also that governments may change their mind. There is some debate as to if energy saving lamps save as much energy as indicated when consideration is made to the reduced heating cost. But also infra-red and other non usable energy is emitted and it seems as yet no research has been as to energy saving when used inside the home rather than outside.

 

[RF Lighting]

Let me get this straight.

You've bought some really cheap lamps, and you're wondering why they dont last long?

 

[pappyon]

When I bought the bulbs about 3 years ago they were a lot more expensive than they are now and surely even a cheap bulb should last longer than 2 minutes.

I don't see any need for sarcasm. It's help I am looking for not personal abuse

 

[RF Lighting]

Who has abused you?

We take that sort of allegation here very seriously, and I will personally write to whoever is responsible and ask them for an explanation.

 

[Spark123]

Is there any sign of damage to the pins on the blown lamp?
What is the stated voltage on the lamp? I take it they are enclosed?

 

[Taylortwocities]

When luminaire makers ship their products with lamps, they supply the cheapest nastiest lamps they can get. it keeps their costs down and you get to buy a product at a "cheap" price.

That's probably why the lamps you were supplied with keep blowing. if you replace the cheap lamps with other cheap lamps then you aren't making the situation any better.

Buying 'branded' lamps (Osram, Philips, etc) may help, but there's no real guarantee; as pointed out above.

Best to replace the GU10 lamps with low energy versions - you'll have to do that sooner or later as the EEC and our nanny state says so.

 

[ericmark]

I have got cheapest of cheap from pound land and no problem. But my sister has bulbs blow on regular basis and she can't rely on compact fluorescents to fire up. All to do with supply. She is on end of line and it has always been a problem. I am mid way and never have problems. Luck of the draw.

So she uses only standard tungsten bulbs and accepts her lot. Maybe she has a lose connection somewhere but when ever I try to help we fall out so I do not get involved.

So three main causes of low lamp life are.
1) Fluctuation of supply voltage.
2) Lose connections.
3) Poor quality lamps.

As to lose connections any lamp which is switched on and off a lot has a reduced life and that is what a lose connection does.

I have found dimming switches do seem to extend to life of standard tungsten lamps. But with quartz halogen lamps one should not use dimming switches as running them at cooler than designed will shorten their life. Stabilising the voltage is only way so power from a UPS or use 12v SELV lamps powered from a switch mode power supply.

But SELV also has problems so there is no answer that will be correct for all situations. Some compromise is required.

 

[SamHandy]

Lamp Life is a bizarre thing. Nor is there such thing as '5 years' lamp, as it will depend on many things such as burning time.

A standard 50w halogen for instance has a 2000 hours lamp life. To explain simply to measure this they get 100 lamps, energise them and when the 50th lamp fails that is the average 'lamp life'. I doubt in real terms they check 100!!

Even if the first 40 lamps failed in the first 10 minutes (unlikely but possible), when the 50th one goes that it, doesn't matter that 5 of them burn't for 3000 hours.

Also depends on outside factors, such as ambient heat.

But it could be something simple for poor lamp life like a dogdy lamp holder arcing. Is difficult to say.

 

[pappyon]

spark 123

I haven't been round to the house yet, but when I do I will check the pins for overheating etc.

The strange thing is I have been using these lamps for years in the house I am in just now, and they have lasted quite some time!

I can understand people saying about cheap bulbs being rubbish, I don't disagree with this. I have bought ordinary bulbs out of Poundland and they literally blew up after a couple of days use, leaving only the bayonet fitting in the lamp socket.

I was merely enquiring if there could be a fault in the light fitting itself.

My apologies to rf lighting for not taking his post in a more light-hearted manner. I was annoyed at the time, but what the heck

 

[bernardgreen]

When you change lamps do not touch the glass with bare hands, use a clean tissue to handle the lamps. At high temperature the miniscule deposits of grease from the skin react with the quartz to trigger a growth of crystal structure in the quartz.

This crystal growth once started continues and weakens the lamp until it either machanically collapses or becomes permeable and allows air into the lamp which oxidises the filament.

 

[securespark]

That only applies if they are not enclosed lamps.