Drawing off two banks thru Switch?

I drew a diagram of the two banks, thru the meter shunt and switch, to the inverter. It seems to me the "both" setting basically turns the two 215Ah banks (A+B) into a series / paralleled 430Ah bank, but with an unbalanced wiring set-up?

2 banks (A+B) side by side, A1 top left, A2 bottom left; B1 top right, B2 bottom right, shunt between A1 and B1:

A1+ to A2-; A1- to 1st shunt post; A2+ to switch pole A.

B1+ to B2-; B1- to 2nd shunt post; B2+ to switch pole B.

2nd shunt post to inverter(-).

Switch common to fuse, then inverter(+).

Comparison:

When switched to "both", inverter draws from both A+ and B+, instead of from one + lead from B2+ (when paralleled to A2+)... negs remain the same as they are paralleled thru the shunt.

(meter + to A2+, meter only tracks bank A)

pianotuna wrote:
Hi jrnymn,

I love my kill-a-watt unit.

I was just looking at them... reasonably priced compared to some. And it would take out all the guess work, I imagine. They come highly recommended by consumers' report, too.

Just bought one from amazon.ca.

Hi jrnymn,

I love my kill-a-watt unit.

Good idea BFL, thanks. And I will compare with the clamp meter. It may be worth my while to buy an appliance meter as well, even just to hook up to the gennie for overall draw?

IMO get a calibration cross-check on that inverter's read-out. It is showing 12xx vice 10xx on that Danby and also your PM4 wattage readings did not match a 45 amper but did a 55 amper.

Not sure how to calibrate that in real life. Switch the Trimetric to watts instead of AH while the inverter is running something?

Roy B. wrote:

"What we have found here is unless both battery groups are fully charged we won't see max performance. Also when one group is down in % of charge it will draw the good side fully charged battery group down to the weaker batteries % of charge." (end quote)


??? Just to be clear, are you referring to when the batts are under load, thru the switch at the "both" setting, or in general with the batts linked thru the switch, but not under load??? thanks.

Aw man. There is a xantrex 1000 on CL for $200.

Hi jrnymn7,

That's amazing, so good on Xantrex.

jrnymn7 wrote:
So far, the inverter has done o.k with the microwave's 1280w draw, running for short stints of up to 3 or 4 minutes (on the 430 bank)... enough time to cook some scrambled eggs the way I like them. It has never set off any alarms, yet.

smkettner wrote:
Load is distributed according to the differential in the parallel circuit resistance.
Clamp on ammeter would give you the numbers.

If the R's are off, (assuming all connections are good), would simply adjusting the cable lengths be an easy fix? Or would individual battery bank health / SOC also come into play? thanks.

Good to see the Xantrex 1000 will operate at 1280W. I have one,too, and think it's a pretty good inverter.