GL: Battery-inverter-charger questions

[Dave Clark]

Jim:

You have some very good advice so far but I would suggest at least six golf
cart batteries which is what I have installed on ADAGIO along with a ProSine
2000. I wish I had eight but couldn't squeeze them in. The main reason is that
while four will take 100 amps charging (a little stronger than I would set it)
they won't take that rate very long before the charger cuts back. You need the
battery bank to be large so that when it's down to where you'll want to
generate (for me about 40% down, 60% full) the bank will accept the max charge
for a long time. This will reduce generator time tremendously. I would guess
you could generate one third the time with eight batteries rather than four.
You need to do the math and it will become clear. Also the batteries will live
a lot longer if discharged only 40% and not hit with more than 20% of capacity
on the charge setting. Some use Capacity divided by 8 as the max charge rate
and actually higher than that should only be done with a temperature sender
feedback to the charger.Another reason to have more is on the smaller battery
bank and the voltage starts to get low (discharged) a very large load will
stress the inverter or trip it because the load you're asking of it will drop
the voltage much more than on a larger bank. Don't ask how I learned this, it
was expensive. Batteries are cheap and more is better.

Dave Clark
ADAGIO
President 41

Have Summer home on an island in the San Juans WA, off grid, two trace  24v
4000w sine waves, 20 golf cart batteries. Runs like on the grid.