On Sun, 7 Dec 2003 19:09:55 -0000, "John" wrote:

Thanks guys.
I thought it may be a difficult one, the fridge is on a trailer (semi) so no
external charging system permitted. Solar had thought of that, and am
looking at a trial.
The 500mA is drawn by the controller and management system, the facility to
be able to have the controller start/stop the fridge from a remote position
was not part of the original manufactures brief (added at the request of the
customer) so no provision was made to power down unnecessary systems.
The battery draws directly from the alternator so no current limitations. To
further complicate the issue, the engine is also capable of start/stop
depending on temperature.
The controller does have a sleep option (restart the unit when battery drops
to 12.2v or engine temp below ox), this would require changes to software.

So in an ideal world, with a new 100Ah charged battery how long do we have
before the battery power is so low that it will not turn the starter and
power the controller.

John.
Minimum should be ~two days Maximum 5-6 days, given a battery in good
shape with a 100 AH capacity, but that's only my guess. Your battery
wouldn't last long in that type of service so the capacity would
probably drop quickly with time.

Solar cells and charge controller would be expensive. Not to mention
that it only takes shade on one cell of an array to limit the entire
panel's output. With a semi, tracking arrays are probably out so
your panel(s) would have to be very large, to compensate for the
amount of sunlight you'd miss. Have to watch where it is parked also.

I think Henry has the best idea - controller battery and starter
battery.

Small propane, or gas powered genset that runs continuously, or runs
when necessary to maintain the battery?

Be nice if there was some chemical means of providing the jolt to
start the diesel. Compressed air starting would be a natural also.

Anything you can do to use less power at the controller?



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----