tlukasavige172 wrote:
4 Duralast batteries that are 12V and in parallel for a total of 340 amps. The batteries are all new within a week.
Right now I'm trying to figure out issues with the 12v bank (Duralast). I have a diesel heater (12V) that I am trying to run which at max is 7 amps (that's full bore and does not constantly run at that rate). From the calculators I found online I should be able to run the heater for 31 hours straight (at that 7 amps) before hitting 50% charge.... Well what I'm finding is when I turn on lights and run the heater my batteries are at 12.27V with a voltmeter reading across the terminals.
1) There are those mysterious "lights"... Regular incandescent bulb draws 1.5A, so a couple of double domes will draw 6A. 13A total. Use
This calculator. Click on the link "Peukert calculator". And read the article itself, that's why I posted it, this is classic. Enter capacity 340 and current 13, and you will get 28 hours to COMPLETE discharge. This makes it roughly 14 hours to 50% discharge.
2) Remember that voltage under load is always lower than voltage on open contacts (i.e. in absence of any loads). To estimate the SOC by measuring the voltage, you should disconnect the loads and give the battery at least 24 hours rest. Voltage will slowly go up after you've disconnected the loads.
tlukasavige172 wrote:
I've read articles of people who say they can run their microwave (or should be able to) for 2 solid hours with the same battery setup as myself.
With 340 AH bank, are you kidding me? MW draws 100 Amps@12V, considering inverter. You'll be lucky to get 1 hour before 50% discharge. And 340 AH bank is not going to like a current that high.
