Any sparkies here?( non boaty)

Appleyard

Appleyard

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Afternoon all.. need a bit of advice re domestic lighting. We have mains halogen lights in the kitchen.. 5 x 50 watt bulbs in total. Problem is they don't last as long as they should.. they seem to die after about a couple of months. These lights are supposed to last much longer surely? There is no insulation above them,therfore they do not seem to be overheating ,also they are not cheapies..they are good quality bulbs,bought from a supplier (CEF) .They always seem to blow on switch on,so I am considering changing the switch to a dimmer switch,which would switch them on gradually. Is this a reasonable idea? Any expert advice appreciated. Cheers!
 
Problem associated with many bulbs in parallel. When cold the resistance of the filament is low allowing a current surge until the filament heats up and reaches it's operating range.

Put many in parallel and the surge is a bit too much. Dimmer should help.
 
Not a sparky, but a landlord who *****g hates halogen bulbs.

I think the biggest cause of failure is touching the glass, (usually during fitting). This leaves a smear of grease from your fingers, which creates a hotspot, causing the bulb to overheat. The long thin bulbs used for floodlights ome with a piece of cloth, and a warning not to touch the glass.

They are also bloody awkward to fit if recessed.
 
Andy ..that makes sense..They are presently wired in a "ring " . Should I wire each one individually from the junction box?
 
Yes I I know not to touch them..I thought I had covered everything in my initial post,but forgot that bit obviously.
 
Switch on surge from bulbs wired in parallel will not affect the lifetime of individual bulbs. Halogen lights do have a relatively short lifetime (something to do with higher filament temperature, I expect). We use them in the shop and end up changing all at least once over the summer season! You could just fit the cheapest possible from B&Q, etc. - lifetime seems to be about the same, but a fraction of the price.

Fitting a dimmer may improve life, not particularly by slow switch on, but by running at less than 100% power/brightness.

On the other hand, you could pay out for LEDs. Not quite as bright, very expensive, but last for ever!
 
Dunno, could be worth a try.

All I know is that like for like, multiple, parallel wired bulbs last a fraction of the time of singles.

It's the same with outside lights, corridor lights, hall/stairs/landing lights.
 
My (our) bedside lights aren't wired in parallel with the centre light fitting over the dining room table, which uses the same 40W clear candle bulbs.

Changing a bulb in the centre light fitting is almost a monthly affair, can't remember when I last changed a bedside bulb. The bedside bulbs prob'ly get used the most as we don't often use that table.

As the centre light fitting is almost certainly wired radially from the hub, it would suggest the issue might be relative to the number of bulbs in the circuit, not the way they are wired.
 
Not sure how relevant this is but trinity house use DC halogen bulbs normally found in OHP's (if you remember them) they are nominally 12v but they run them at 10V (every night!!) to quote one of the attendants "I've never had to change one yet". So I would say that a dimmer is probably a good idea.
 
We’ve done this before I reckon its vibration – room above people tramping around ? I have one or two halogen bulbs in my house that have lasted 15 years, most go in months just like you.


[Re parallel – perhaps wring back to power station would help?
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Some thoughts

I too have bought Halogens from CEF, but you still need to be sure of what quality you are getting. CEF will be selling both bargin-basement get you going jobbies as well as good quality longer life versions. Ask.

The other comments regarding handling halogen bulbs, and not subjecting them to movement while on are all valid. Also, regular turning on and off _may_ shorten their life, although I've never heard of this one.

Regarding random bulbs that seem to last forever - I think you are just lucky and have got some top 5% percentile bulbs there. All things are manufactured to a 'tolerance'. Some will last longer than others, give better light than others, etc. Occasionally you'll come across a bulb with a shorter, or a longer, life than normal.
 
Trust me I am a sparkie!

CEF i consider the Woolworths of the electrical wholesale business....usually selling cheaper versions of stuff at regular prices.

Try a "soft start" dimmer..MK for example. Dont think CEF sell MK....
 
If Your bulbs are mounted in the cieling the most common cause of poor lamp life is due to the vibration caused by movmeny on in the rooms above. Have been fitting both ELV and LV halogen lighting for years and have always notifide customers that the lamps are no more robust than normal incandecent lamps, I am sure we all know what hapens when you knock the laed lamp to hard. Try CEF and ask for shock resistant lamps, but you will wince,
 
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