"Scott Badman" wrote in message
...
"DoUbLeStUf" wrote in message
news The halogen headlamps in a motor vehicle function differently to the
incandescent blubs in your home. The halogen bulb is a hive of activity
with bits of the filament breaking away, then refusing, breaking away,
refusing, etc etc in a continuous cycle.

When the lamp runs under voltage this fusing process doesn't take place
properly, causing wearing of the filament. Hit the lamp with full voltage
again, and the deteriorated filament can not handle the current, and
blows.

The constant vibrating forces present on the globe don't help either



I highly doubt the magic composition of halogen lamps in the automotive
environment differ from those used in professional lighting applications and
homes where they are dimmed all the time. In pro apps the lamps are almost
NEVER full tilt. I have found them to last longer dimmed. As long as that
baby is making light this chemical process is happening. I imagine it's a
fairly linear function. I suspect vibration and voltage overshoot.

Chad