What would cause a halogen bulb to explode?

BatteryCharger

Flashlight Enthusiast
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Jun 5, 2003
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The crazy guy next door
Earlier today I was working on installing a remote starter on a generator. Since it's designed for cars, I had to temporarily hook up "parking lights" to the circuit to get it to work. I used a 35w halogen sealed beam headlight for this. After it was on for about a minute, the bulb exploded!

What the heck would cause it to do that? There's no way it could have gotten a voltage spike, and it didn't get any water or anything on it because it's a sealed beam. Kinda makes me wonder how dangerous my 500w halogen work lights are...:eek:oo:
 

z282z06

Newly Enlightened
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Apr 11, 2007
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I have heard that you can get oil on them, even from your hands and that will cause them to get a hot spot where the oil is and cause a failure of the explosion scenario. If you look at the directions on those "hot" bulbs they always tell you to handle the bulb with tissue paper to avoid oil transfer.
 

65535

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Temp variations in the bulb envelope can cause shattering and with high internal pressures it goes off like a firecracker. Normally that is caused by poorly made lamps with uneven envelopes, or if oils got on the bulb, rarely can it be caused by physical contact of the bulb housing, and it water did get on the hot bulb it could fracture.
 

LED-FX

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Jul 23, 2001
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Edinburgh UK
Other part of halogen lamp is quartz envelope, quartz glass is soft but can stand heat clser to filament that standard glass.

Ctach being that if it gets fingerprints or anything on it , the grease from the fingerprint will boil and the soft glass will bow out with the internal pressure, some you see with a big bubble out the envelope.

This can lead to exploding,er, non passive failure of the lamp.

If you do get fingersprints on a lamp, gently clean with mets or very pure ethanol.

Cheers

Adam
 
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