A simple question about - Bulbs

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sooty
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A simple question about - Bulbs

Post by sooty »

A simple question, what causes bulbs to go black after a short time ie: tail lamp ?? A fault or quality of bulb.
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Kered
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Post by Kered »

Bulbs go black as the tungsten filament "boils off" as a vapour and is then deposited on the glass as a dark stain. So the black was once part of the filament. The tungsten is glowing white hot in order to give the needed light. IF it goes black in a short space of time it is most likely that the applied volts are too high - so running the filament at a higher temperature than is desirable causing premature blackening. Cheap bulbs could be so poorly specified that they blacken at normal volts.
Derek
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AndersDK
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Post by AndersDK »

Agree with Derek - a common problem with cheap lo quality bulbs.
Stick to wellknown branded bulbs - they are not that more expensive.
Often the gas stations offers lo quality bulbs at insanely high cost - as you don't walk around town just to find a simple replacement bulb.
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