Solar panels not producing.

[Wrivera]

Hello,

I am outside of Phoenix, AZ, and my solar panels are set at approximately 23 degrees facing south.

I have 3 strings of 9 400W bifacial panels (for up to 495W). Each string wired and in series. Newly installed.

I have 2 6000xp off-grid inverters.

When reading the inverters during the day the most I have seen coming in on any of the strings is 700W/h. It is more typical to see only 100 to 160W/h per string vs. (9×400w=3600w/h) I could potentially be seeing per string.

What could be the issue? I washed the panels so they are not dirty and it certainly hasn't been cloudy lately. I am pretty stumped...

I am not an expert in any means I have only a very basic understanding of how this stuff works.

For a little additional information I am constantly seeing 300+V per string. The panels have an 38 VOC so seems pretty in line with what I should seeing.

 

[wpns]

what panels and what are their complete specs? And how exactly are they wired?

 

[solaruser120]

The power from the PV will be dependent on the load and the battery's ability to accept charge (or charge limits set on the inverter). Is there a sufficient load? You'll see the PV voltage go up when the PV power is limited by the load (when not operating at the maximum power point).

 

[Wrivera]

what panels and what are their complete specs? And how exactly are they wired?

 

[Wrivera]

The power from the PV will be dependent on the load and the battery's ability to accept charge (or charge limits set on the inverter). Is there a sufficient load? You'll see the PV voltage go up when the PV power is limited by the load (when not operating at the maximum power point).

That makes sense. I have a very limited load on it right now. Pretty much just shop lights.

I am trying to test my heat pump central air but I am also trying to troubleshoot that currently as well. (Power isn't making it to my air handler)


But I am also having trouble with it charging my battery bank as well. The batteries are shown on the inverters but they are not sending any current to charge.

So if I am understanding you as I increase load on my system I will see more kwh coming in to the inverters?

 

[solaruser120]

That makes sense. I have a very limited load on it right now. Pretty much just shop lights.

I am trying to test my heat pump central air but I am also trying to troubleshoot that currently as well. (Power isn't making it to my air handler)


But I am also having trouble with it charging my battery bank as well. The batteries are shown on the inverters but they are not sending any current to charge.

So if I am understanding you as I increase load on my system I will see more kwh coming in to the inverters?

Yeah and you'll also see the voltage drop down closer to the Vmmp * 8 ~= 279.45 V (depending on the panel temperature and solar irradiance)

You might want to get the battery bank working before trying to handle big inductive loads (I'm not sure how fast the PV controllers can react to large demands)

Are you using the battery communication cable? or just doing a voltage control? (Lead-acid mode)

 

[littleharbor2]

In a nutshell, are your batteries fully charged? If so there will be very little pv power going to them.

 

[glandpuck]

A short course in PV:

Power flows from the panels to either A: the batteries to charge them, then to the loads and then to any selling to the grid if allowed. In this case, if the batteries are fully charged, the loads are very small and the grid selling is small or disabled, then no PV is harvested becasue there is no work to be done.

In scenario B: PV flows to the loads, then extra PV flows to charge the batteries and finally PV is sold to the grid if allowed. In this case, if the loads are met, the batteries charged, and selling not allowed, the PV will be reduced or be very small or even shut down under very small load conditions.

In both of these "cases" the PV will pop on and off as the logic of the inverter controls the power and there can be delays in the reaction, its not speed of light fast.

 

[Wrivera]

Yeah and you'll also see the voltage drop down closer to the Vmmp * 8 ~= 279.45 V (depending on the panel temperature and solar irradiance)

You might want to get the battery bank working before trying to handle big inductive loads (I'm not sure how fast the PV controllers can react to large demands)

Are you using the battery communication cable? or just doing a voltage control? (Lead-acid mode)

It's connected with a battery communication cable.

I have https://signaturesolar.com/eg4-ll-s...enclosed-rack-with-door-wheels-busbar-covers/

I need to check my settings. I know I have it set on lithium-ion and it should be default for the reaming settings right now (in regards to the battery settings).

Batteries are currently setting at 55%. That is what they were at when I first turned them on.

 

[Wrivera]

In a nutshell, are your batteries fully charged? If so there will be very little pv power going to them.

They are not. They are about 54-55% which is where they were against at when I first turned them on.

 

[solaruser120]

I think this might be a decent video that goes over the battery communication setup:

(I know there's another video that explains it better, but I couldn't find it)

I don't have an EG4 6000XP (an 18kPV which is similar but not quite the same)
To change the communication protocol settings on the master battery I think it requires 0 voltage on the battery terminals (at least it did on the EG4-LL V1 and V2, I don't have any of the new S version batteries) or maybe that was to update the firmware -- I don't remember since it's been awhile since I did that. (Oh and power cycle the BMS when changing the dip switch address)