RoyBoy posted:Adriatic posted:It burns twice as bright and lasts half as long on 24v. (The heat range is something you need to check. It can occasionally not be what's expected, so I'm not even going eleborate on the "norm" because it has bit me before.
I think it's more of an exponential curve than a linear curve.
Very much so. It's full of variables. Once at our extremely low voltage, it's close enough to fudge more. Lower volts have thicker filiments. Long life vs normal life would react differently too.
A 120v bulb on a 110v feed would nearly double life.
Ac vs dc is a toss up too. Ac may vibrate more breaking the tungsten, but is allows more cooling. DC currents will be higher. Throw in a gas bulb like halogen vs a vacuum and too low a temp. will effect the tungsten's life as the halogen needs to get hot to work right. Underdriving lowers efficiency.
"Good enough" for a general understanding of what to expect; the heat retention differed from my expectations only twice that I encountered. I melted two pinball bumper tops because I didn't check the heat build up before I closed up. They were underdriven for sure. (18v fed 12v if I recall; but might have been 12v bulb @ 6v..? That was 15+ years ago.)(I had to change a few mini's daily, maybe 5-10 daily in a "spikey" week...about 100-150 a month average, 6-24v ac/dc, chopped drivers and sine. Too trivial to fret much when a few minutes, eyes and fingers tell the story for each case.)
