Thread: Light Bulbs Blowing out constantly

what sort of light fittings are they?

Just your standard bayonet type light globe. 40W, 60W, 75W, whatever. I'm not talking halogens or anything here. Just standard 240V light globes.

This happened to me - I'd be buying a couple of light globes a week. It happened to the lights on the light circuit as well as lamps on the power circuit. No pattern at all. Nothing to do with the weather or anything else I could think of.

There was never a problem in the house we moved from but it was consistent over the 14 years since we moved to a new suburb. (The reduction in street crime more than made up for the light globe problem.)

I asked a few sparkies and couldn't get any to show the slightest interest or suggest how I might fix the problem. One suggested rewiring the house but couldn't tell me why that might work, or even give some estimate of the odds that it might do some good, let alone guarantee it.

Anyway, I changed to those new long life globes progressively as the old ones blew and haven't had any problems for ages. None of the new ones have failed. So far, so good.

I still don't know why it happened and I'd be interest to hear any theories.

I thought it might be something to do with how close my place was to one of those big transformer thingies or whatever they're called.

Gaz.

Are these lights enclosed? I found heat to be the biggest killer, even if they have little ventilation holes which are next to useless. I'd used to go through a couple a month. It was crazy. I also found that the latest globes seem to be very fragile compared to the older globes they used to make. The element seemed thinner etc. I then switched to the energy saver globes and not a single issue since since they run cool. I won't be going back to normal globes anytimes soon.

PS: I had the house rewired and still the same problem. I didn't rewire it because the lights were blowing but there just weren't enough circuits to handle the household load + the protective sheeth around the wiring was disintegrating giving me the worry that I would be caught sleeping in an inferno.

We had the same problem with a new house (18 years ago) and also with toasters (6 months life) and jugs (4 months). We eventually went for the heavy duty light globes and they did not blow out. In the meantime we had an extra circuit put in for power and the electrician looked over the electrics of the place. Since then we have had minimal appliance deaths and since the advent of the power saving bulbs, few light blow outs. touch wood!

Carry Pine

Have you measured the supply voltage? Over voltage will cause them to blow.

Is the house in an area where it is being vibrated by road, rail or air traffic or some other form of vibration such as an airconditioner? Vibration will break the filaments.

wood borer makes a good suggestion... a 5% increase in voltage leads to a 50% reduction in bulb life.

is their house near a railway line, main road or some other area with heavy machinery? vibrations can be a killer too. try RC[rough construction] standard bulb, they are designed for areas of high vibration or mechanical movement, and may last a longer than your standard.

is the house in a new area? quite often, the first few houses will suffer from slight overvoltage as the supply transformer is tapped higher than it should be in anticipation of a growing load.

try getting up in the roof if you can and clearing insulation away from where the globes exist. this will encourage heat disapation [95% of energy used by incandescent globes is given out as heat] and hopefully prolong the life of the globes.

go out to the meter, and if it's a digital type, should have a voltage reading. i'd be concerned if this was above 245v. if it's an analogue, too bad get a sparky in to take voltage readings. if you specify that you'd like him to fix the problem, you would arguably only have to pay for anything that does rectify the problem.

On another post in the past month or so (might have been a different sub-forum, maybe WoodTurning - General), a bloke had trouble with fluctuating voltage damaging his equipment. Fluctuating voltage can have the same effect as vibration in reducing fatigue life. Power supplier or a sparky may be able to record voltage over time. Meanwhile, heavy-duty bulbs might help.

Joe

Originally Posted by joe greiner

On another post in the past month or so (might have been a different sub-forum, maybe WoodTurning - General), a bloke had trouble with fluctuating voltage damaging his equipment. Fluctuating voltage can have the same effect as vibration in reducing fatigue life. Power supplier or a sparky may be able to record voltage over time. Meanwhile, heavy-duty bulbs might help.

Joe

FYI if you can prove bad fluctuating voltage damage you can actually claim against the electricty provider for damages. Check you provider to verify but with my one I can.

Thanks for all the replies there. I seriuosly think it is more a supply votage issue.

Koala-Man: it happens on both lights on the light circuit and mains circuit. As fridge light blew out twice, garage opener light blew out and so did lights in baton holders in the ceiling. Also, about changing to better branded globes, made no difference. They still blew out.


Montiee: There are bulbs both enclosed in glass shades and ones that aren't. No difference. Energy saver, same thing, two of these already blew out. Energy savers were only a couple of months old.

Carry Pine: The house was built in 74 so the wiring is still not too bad. Its not the old style stuff anyway. As far as putting more circuits on the place, maybe that's what it needs. Not sure. I'm still leaning towards over voltage. Its like the bulbs are fed too much current at the flick of the switch and they blow. I made sure their new plasma had a surge protector installed though. That would be a painful loss.

Wood Borer: I haven't had the voltage measured, but will. As for vibration, unlikely. It is a single storey brick veneer. Admittedly it is on stumps, but pretty solid. And it is no where near railway. It is in a flight path but not close enough to an airport to cause vibrations.

Fortunately there's been no major damage (yet), only light bulbs. Although their fridge broke down a while back...but that could be anything. I think I will urge them to get a sparky in to measure the voltage. What's the best way to ask the sparky? There probably wouldn't be much in it for him if it is a bad transformer ont he road. I take it I will have to pay for his services and then reclaim from electricity company if there is a problem I suppose.

Thanks for all your input peeps.

Dan.

Having spent 13 years working on traffic lights, I've changed a bulb or two... Actually, I'd estimate that it's in the order of 25,000 that I've changed.

Bottom line is problems generally are caused by one of these. All except No. 2 are quite likely to happen at home.

1. Excess heat building up
2. Water or other liquid coming in contact with the hot globe
3. Vibration breaking the filiament
4. Poor quality globes
5. ES globes not screwed in far enough
6. Voltage is too high.
7. The problem is not the globe but a faulty lamp holder. Replacing the globe moves the contacts thus temporarily fixing the problem. Simply taking out and re-inserting the same globe would provide the same temporary fix.
8. Short running. One particular brand of bulb had a problem where the internal fuses would blow when the bulb was only run for short periods. This resulted in all the amber traffic lights blowing but not the red or green where identical bulbs were installed (the bulbs themselves are not coloured). The underlying issue related to thermal expansion as the globe heats up.