This has probably been discussed before. I am not a fultimer. What I was wondering was if you ran your 12v stuff off your battery and ran an inverter, and ran a battery charger off your inverter what would keep it from working like this for a couple of days.

You mean like a perpetual motion machine? Use an inverter that is draining the batteries to charge the batteries?

Yes, sort of like that. I would like to use the battery for lights, radio, etc. This probably would not work, but was wondering if it would for a couple of days?

I think the inverter will drain the batteries fairly quickly...much quicker than if you just used the batteries alone.

You really don't want to know how inefficient inverters and chargers are. Just for numbers let us say the inverter is 90% efficient, which is possible if the inverter is being loaded well, and the charger is 90% efficient, which is probably better than most chargers. That means that you take 10AMP out of your battery and only get back 0.9 times 0.9 time 10 or 8.1 AMPs back in. If you have a 40AMP charger than it needs about 50AMPs from the batteries to run, so every hour you lose 10AMP-hours. Those batteries are getting used by your lights, your water pump, etc., so you are taking an extra 10AMPs per hour out of your batteries than leaving it be.

-- Edited by bjoyce on Wednesday 2nd of March 2011 11:12:28 PM

Thanks bjoyce, that answer makes sense. I knew that it probably would not work, but did not know why.