Two 6 volt batteries or two 12 volt batteries ??

SoundGuy wrote:

lawrosa wrote:
OK.. So I am able to run say my toaster oven now. Even @ 12.5 volts the drop dont go much below 12v..

So your saying if I went 6 volt and had the batts @ 12.5 and put a 800 watt load on the voltage would drop below my 11.5 inverter cut off?

You're trying to apply specific numbers to a situation chock full of variables so no one can give you a definitive answer. A better way to look at it is this - one scenario you have two 6 volt GG-2s connected in series and 20 Hr rated @ 220 AH as a pair, under a second scenario you have two G31 12 volt batteries connected in parallel and 20 Hr rated @ the same 220 AH as a pair AND in both scenarios these batts are connected with the same gauge & length of cable. Compare the two setups and you'll find the 12 volts will suffer noticeably less voltage drop under the same load than will the 6 volts because internal resistance of the 12 volts is much less than the thicker plate 6 volts. Likewise if you use 12 volt AGMs instead of 12 volt flooded the results will be even better. Voltage drop isn't only about running the batts themselves down but shutting down the inverter when input voltage drops below it's operating limit which is determined by the manufacturer and will vary somewhat from one inverter to another.

I have 3 75 ah duracells in parrelel.. Actually one is a 70 ah... so 220 ah's. But the batts are getting old and I will probably replace this summer..

was thinking 6 volts but I dont want my inverter to suffer..

Oh im sorry its

Under Voltage Shutdown Under 10 VDC
Low Voltage Alarm Audible at 10.6 VDC

LOL last year I had the alarm going off in morning when wife making coffee. But I had challenged charging abilities then.