On the very lengthy "Lamp Questions" thread, I noted a quote by Ship:
So this means, if I want to get a lot of life out of my lamps, but really aren't concerned about the hottest of light or the brightest, I could trim my dimmers to max out at say 118v at full, and get more hours out of the lamps.
Somewhere I heard that for every volt you deviate from the rated voltage, the life inversely changes by 12%. That means if you run a 120V 1000-hour lamp at 121V, it would be a brighter 880-hour lamp. And if it were run at 119V, it would be a 1120-hour, but less bright lamp.
Also, with regard to the tungsten-halogen reaction, at what level (generally) does the filament get cold enough to were the reaction stops taking place?
The following rule of thumb can be derived:
A 5% change in voltage applied to the lamp results in
- halving or doubling the lamp life
- a 15% change in luminous flux
- an 8% change in power
- a 3% change in current
- a 2% change in color temperature
So this means, if I want to get a lot of life out of my lamps, but really aren't concerned about the hottest of light or the brightest, I could trim my dimmers to max out at say 118v at full, and get more hours out of the lamps.
Somewhere I heard that for every volt you deviate from the rated voltage, the life inversely changes by 12%. That means if you run a 120V 1000-hour lamp at 121V, it would be a brighter 880-hour lamp. And if it were run at 119V, it would be a 1120-hour, but less bright lamp.
Also, with regard to the tungsten-halogen reaction, at what level (generally) does the filament get cold enough to were the reaction stops taking place?