This is from memory, I'll dig out the text when I get home and add post then. It's from "Electrical Wiring - Commercial"
(Rated Voltage/Actual Voltage)^13 = (Actual Life/ Rated Life)
e.g. Assuming a bulb rated 130v and 1000 hr and receiving 123 volts ...
(130/123)^13 = (X/1000)
2.054X=1000
X = 2054 hours of actual life
In reverse: 120v 1000hr rated and receiving 123 volts
(120/123)^13 = X/1000
.725X = 1000
X= 725 hrs actual life
I'm home now and the formula is correct.
The text is "Electrical Wiring Commercial" Ray Mullin & Robert Smith (Delmar publishers)
It's in unit 14 if you have the book
[This message has been edited by Steve Miller (edited 02-11-2005).]
