2 different sized solar arrays for 2 LVX 6048. The small one cuts power under bright conditions?

[Brettw]

I have 2 different solar arrays, one is 5520 watts, 6s 2p running on 2 wires down to the house to 1 LVX 6048. The other is 1440 watts, 6s running on the other 2 wires to a 2nd LVX 6048. When the sun comes out strong the small array cuts wattage power down to basically nothing, but when it's cloudy they both put out power and send charge to the batteries. Is this caused by a short between the wires or is the smaller PV array not able to push amps at the same time as the large array?
The large array can push 80+ amps into the batteries when the sun is bright.

 

[mib]

if both LVX have the same floating charge voltage, it may be the length, the resistance of the wires from the LVX to the battery, and when there is a lot of sun, the current is not divided evenly, but only one works, when there is little, two work

 

[Brettw]

if both LVX have the same floating charge voltage, it may be the length, the resistance of the wires from the LVX to the battery, and when there is a lot of sun, the current is not divided evenly, but only one works, when there is little, two work

All the wires from the battery to the LVX's are the same length. But to what you said, I can get 80 amps from the large array going into the battery, while the small array has yet to put out more than 5 amps before it gets cut off by the difference between them.

 

[brum]

With provided information I would assume the following - these are batteries not communicating with the inverter and each inverter is configured to control the charge based on the voltages. The inverters are using different voltages to control the charging. Once the larger array is pushing these 80 amps the voltage is getting higher enough to reach some of the thresholds for the inverter connected to the smaller array.

To confirm and fix the issue - check the charging settings of both inverters. Configure them to be identical and correct.

 

[mib]

an error of 0.001 volts is enough, I have the same problem, if I raise a floating charge by 0.01 volts on something that does not work in bright sun, the first one stops working

 

[Brettw]

With provided information I would assume the following - these are batteries not communicating with the inverter and each inverter is configured to control the charge based on the voltages. The inverters are using different voltages to control the charging. Once the larger array is pushing these 80 amps the voltage is getting higher enough to reach some of the thresholds for the inverter connected to the smaller array.

To confirm and fix the issue - check the charging settings of both inverters. Configure them to be identical and correct.

This makes since because I just brought the 2nd inverter online and haven't done any configuration on it yet. Thank you.

 

[brum]

an error of 0.001 volts is enough, I have the same problem, if I raise a floating charge by 0.01 volts on something that does not work in bright sun, the first one stops working

Kind of expected with an incorrect setup. There are a few ways to properly solve this:
1) Get a battery with BMS that talk to the inverter and dictates the charging. Likely not applicable to lead-acid batteries.
2) Wire the inverters to talk to each other and work in sync. Inverters with proper software should handle this.
3) Use a separate battery bank for each inverter.

 

[mib]

@brum voltage settings are the same, wire length is the same

in my case in bright sun, the sun panels can give out 1200 watts, my need is always 200 watts

the point is that when the sun is bright, one mppt controller works, covering the entire load, the second is resting, there is no uniform distribution of 100 + 100, one copes gives 200 watts

on cloudy days they both give 100 + 100 watts

it's a matter of millivolts, and the redundancy of my solar station in relation to the load

in my case, this is not a problem, rather a feature, but I wrote about this to the author of the topic, thinking that he had the same situation with millivolia, but it turned out everything was much simpler and all I had to do was make the right settings