Lamp failure
Lamp failure
(OP)
What are the most likely causes of premature lamp failure in domestic lighting system.
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RE: Lamp failure
RE: Lamp failure
RE: Lamp failure
The loose connections can create thermal stress as well. Tungsten also has a positive coeficient of temperature, meaning that as temperature goes up, the resistance goes up. When you first turn it on, it is cool so the resistance is lower and therefore current tends to be high for a few milliseconds. That heats it up quickly so it reaches operating stasis and glows accordingly. If a loose connection is "flickering" the tungsten on and off rapidly it actually cools ever so slightly in between and the resultant spikes in current raise the instantaneous temperature beyond the design limits. Over time those temperature spikes cause minutely more vaporization of the tungsten and shorten the overall life.
It is all based on the same basic principal of electrical components:
Heat x Time = Failure.
Probably more than you wanted to know but there you go.
"Venditori de oleum-vipera non vigere excordis populi"
RE: Lamp failure
I would have given you a star, had you been able to spell vapour and its derivatives in the way the Queen recognises. But good post anyway!
-----------------------------------
Start each new day with a smile.
Get it over with.
RE: Lamp failure
RE: Lamp failure
ScottyUK,
I use MSWord for spell-checking, and Bill Gates says that it is spelled VAPOR. It even goes so far as to highlight VAPOUR as being misspelled. Your Queen no longer has as much money (est. $420 million) and power as Mr. Gates (current net worth $56.89 Billion, controls most of the personal computers in the world), therefore in true American fashion I succumb to the richest authority.
By the way, MSWord also does not recognize your "recognise" either.
I gave you a star anyway because I like your style...
"Venditori de oleum-vipera non vigere excordis populi"
RE: Lamp failure
RE: Lamp failure
RE: Lamp failure
RE: Lamp failure
As a side note:
Light bulb analysis is a tool used by accident investigators. They can determine if a light was on or off at the time of an accident, because tungsten is a ductile material when hot and stretches while when cold it is brittle.
RE: Lamp failure
The problem was about lights - not spelling.
I suppose this comment is wasted space and time as well.
RE: Lamp failure
aviat - read between the lines.
skiier - chill out!
RE: Lamp failure
TTFN
RE: Lamp failure
RE: Lamp failure
Good point. I forgot the "ceiling fan" factor. Incandescents on vibrating or moving equipment are indeed susceptable to premature failure. Generally, thicker filaments and/or more supports are used on application specific bulbs for this. But many people don't realize why a "ceiling fan" bulb costs more than a standard bulb, so they put the cheaper one in the fan and complain that it "burns out too quick".
Amptrap,
I too am always amazed at how many people equate a dour attitude with professionalism. I (obviously) like keeping my tonque firmly in my cheek at all times. It stops me from drooling all over myself.
"Venditori de oleum-vipera non vigere excordis populi"
RE: Lamp failure
-Pete
RE: Lamp failure