"tdacon" fired this volley in
:

I'd like to be able to measure how many hours in a
day it runs, without having to sit there and time it when it turns on
and off. How would you go about that?


12VDC hour meter. You'll have the duty of recording and subtracting daily
times, but even if it ran for a week before you 'serviced' it, you'd still
have an average. And it will give you a relatively accurate total time.

http://www.mcmaster.com/#1877t81/=u6lif5

LLoyd