My first off-grid solar system 3400 watts but need advice to reach potential

[kymatt19]

So my first system....and at best it powers the off grid cabins needs half the day into half the night. It should do it all the time. I'm going to replace the 8 awg cca battery cables I made with 4 AWG pure copper. But in the mean time .... what else appears a miss here....

System includes:
9 x 300w panels
2 x 200 watt panels
3 x 100 watt panels
12 x 100 Ah Lead Acid Solar Batteries
2 x 4000 watt pure sine inverters
1 Fuse box
1 400w wind turbine and controller
3 x 80 amp solar controller
20 amp solar controller
60 amp solar controller
1 battery monitor

 

[sunshine_eggo]

100Ah * 12V * 12 = 14,400Wh total battery capacity

900W/12V = 75A charge current

75A through 10awg is WAY too much.

Consult an AWG chart for proper sizing.

Are the charge controllers PWM and are the panels in parallel?

Are your panels facing due South?
Are your panels tilted appropriate for your latitude?
Are your panels free from any shading of any kind from dawn to dusk?

Have you checked that each and every connection in the system is properly tightened?

If you really have 3400W/12V = 283A, yeah... 8awg is too thin as is #4. Battery interconnects are usually quite beefy. Given the current, I would use 4/0. Given the outrageous current, you're likely hammering the living hell out of the batteries closest to the chargers and losing massive amount of power to thin wires.

 

[Bvillebob]

A couple of 4000 watt inverters are probably bleeding half your capacity just sitting here doing nothing. Have you looked at your idle power draw numbers?

 

[pollenface]

I would reconfigure the batteries so that they're all connected evenly with the same cable lengths to a common buss bar shared by all loads and charge controllers and delete the inverter that doesn't work over 200w.

If your wiring is the same as what's in the picture the first 2 batteries are getting hammered and the last 2 probably aren't doing anything.