Help me diagnose my system

[McDubsy]

I need help diagnosing my system.
It doesn't seem to be putting out the power it should.

System is as follows:
-2,600W solar array ( 8 panels each are 325w-10a-40v panels)
-Renogy Rover 100A MPPT Charge controller
- 12v 600ah lithium battery bank
- renogy 2000W inverter
Wiring is good, oversized slightly. There is almost no loss of power at the charge controller in relation to what is put out at the panels.

My average output for the entire array is about 300w/hour measured at the panels.
This seems way low.
When tested at the panels, they are producing the correct amount of volts but their amps seem low. They only put out 2 or 3 amps per panel and 4 to 6 for the entire array. I have 4 sets of 2 panels (series) wired in parallel. Sorry, I don't know how to better say that.

My orientation and angle is good, there are no obstructions it gets full sun all day.
I have had times where I get 600 to 1200 w generating in the mornings when it is cool.
However that does not last for more than about 40 minutes. The panels heat up significantly and the output drops.

Is it realistic to only be getting 15% or rated output?
I would expect more like 50 to 70%.

I would love any help or trouble shooting tips you guys can give me. I'm happy to send pictures as well.

 

[fromport]

I need help diagnosing my system.
It doesn't seem to be putting out the power it should.

System is as follows:
-2,600W solar array ( 8 panels each are 325w-10a-40v panels)
-Renogy Rover 100A MPPT Charge controller
- 12v 600ah lithium battery bank
- renogy 200W inverter
Wiring is good, oversized slightly. There is almost no loss of power at the charfe controller in relation to what is put out at the panels.

My average output for the entire array is about 300w/hour measured at the panels.
This seems way low.
When tested at the panels, they are producing the correct amount of volts but their amps seem low. They only put out 2 or 3 amps per panel and 4 to 6 for the entire array. I have 4 sets of 2 panels (series) wired in parallel. Sorry, I don't know how to better say that.

My orientation and angle is good, there are no obstructions it gets full sun all day.
I have had times where I get 600 to 1200 w generating in the mornings when it is cool.
However that does not last for more than about 40 minutes. The panels heat up significantly and the output drops.

Is it realistic to only be getting 15% or rated output?
I would expect more like 50 to 70%.

I would love any help or trouble shooting tips you guys can give me. I'm happy to send pictures as well.

First thing that comes to mind: are your batteries full?
If there is no where to go with the energy, it is not being generated in the first place.
2600 watt PV power with only a 200 watt inverter ? isn't that a typo and should that be 2000 watt ?

 

[McDubsy]

First thing that comes to mind: are your batteries full?
If there is no where to go with the energy, it is not being generated in the first place.
2600 watt PV power with only a 200 watt inverter ? isn't that a typo and should that be 2000 watt ?

My batteries are at 40%
Under full load, 800w ac unit, I only get 350w max output from the array.

And yes. The inverter is a 2000w inverter.

 

[John Frum]

I need help diagnosing my system.
It doesn't seem to be putting out the power it should.

System is as follows:
-2,600W solar array ( 8 panels each are 325w-10a-40v panels)
-Renogy Rover 100A MPPT Charge controller
- 12v 600ah lithium battery bank
- renogy 200W inverter
Wiring is good, oversized slightly. There is almost no loss of power at the charfe controller in relation to what is put out at the panels.

My average output for the entire array is about 300w/hour measured at the panels.
This seems way low.
When tested at the panels, they are producing the correct amount of volts but their amps seem low. They only put out 2 or 3 amps per panel and 4 to 6 for the entire array. I have 4 sets of 2 panels (series) wired in parallel. Sorry, I don't know how to better say that.

My orientation and angle is good, there are no obstructions it gets full sun all day.
I have had times where I get 600 to 1200 w generating in the mornings when it is cool.
However that does not last for more than about 40 minutes. The panels heat up significantly and the output drops.

Is it realistic to only be getting 15% or rated output?
I would expect more like 50 to 70%.

I would love any help or trouble shooting tips you guys can give me. I'm happy to send pictures as well.

You charge controller is way over-paneled.
I reckon the most you can get from the charge controller is ~1400 watts.

My batteries are at 40%
Under full load, 800w ac unit, I only get 350w max output from the array.

Do you have any shading on the panels?
Are they dirty?
Is the panel angle optimal?

 

[fromport]

My batteries are at 40%
Under full load, 800w ac unit, I only get 350w max output from the array.

And yes. The inverter is a 2000w inverter.

How are your panels connected to your Charge Controller?

 

[McDubsy]

You charge controller is way over-paneled.
I reckon the most you can get from the charge controller is ~1400 watts.

Do you have any shading on the panels?
Are they dirty?
Is the panel angle optimal?

Yes. I live in the UP of Michigan so I need to be over paneled to survive the darker winters.

I would agree with you, however, even at peak sun and depleted bank, I never see 1400w.

 

[McDubsy]

How are your panels connected to your Charge Controller?

I have four sets of two panels. Each set is wired is series and the four sets are wired in parallel. That final positive and negative go through a fuse breaker and then directly into the charge controller.

 

[McDubsy]

You charge controller is way over-paneled.
I reckon the most you can get from the charge controller is ~1400 watts.

Do you have any shading on the panels?
Are they dirty?
Is the panel angle optimal?

Panels are clean. No shading all day long
Angle is 35 degree.

 

[fromport]

I have four sets of two panels. Each set is wired is series and the four sets are wired in parallel. That final positive and negative go through a fuse breaker and then directly into the charge controller.

According to what I kind find on https://www.renogy.com/content/RNG-CTRL-RVR100/RVR100-Datasheet (non-Li).pdf
the renogy rover is not a charge controller for li-ion batteries. What kind of BMS do you have on your batteries?

*EDIT*
According to https://www.renogy.com/rover-100-amp-mppt-solar-charge-controller/


Automatically detects 12V, 24V, 36V and 48V DC system voltages (for non-lithium batteries).
Compatible with various Deep Cycle battery options: AGM, Sealed, Gel, Flooded and Lithium.

That is a bit confusing...

 

[John Frum]

Can you please post a picture of the core of your system?

 

[McDubsy]

According to what I kind find on https://www.renogy.com/content/RNG-CTRL-RVR100/RVR100-Datasheet (non-Li).pdf
the renogy rover is not a charge controller for li-ion batteries. What kind of BMS do you have on your batteries?

*EDIT*
According to https://www.renogy.com/rover-100-amp-mppt-solar-charge-controller/


Automatically detects 12V, 24V, 36V and 48V DC system voltages (for non-lithium batteries).
Compatible with various Deep Cycle battery options: AGM, Sealed, Gel, Flooded and Lithium.

That is a bit confusing...

That's super confusing. Haha. In the SCC settings it has an option for Lithium. So, that's what Ive set it to.

My battery have a 200a bms

 

[McDubsy]

Can you please post a picture of the core of your system?

Sure. What do you mean by Core?

 

[400bird]

I'd start by separating out each string (of two panels), measure open circuit voltage and short circuit current.
Then connect each string one at a time to the controller to test output.

Also check the polarity. You could have one string or single panel. backwards.

Lastly, you're way over the spec sheet recommend max PV. If I read it right, max PV is 1300 watts. You've got double that!

 

[McDubsy]

According to what I kind find on https://www.renogy.com/content/RNG-CTRL-RVR100/RVR100-Datasheet (non-Li).pdf
the renogy rover is not a charge controller for li-ion batteries. What kind of BMS do you have on your batteries?

*EDIT*
According to https://www.renogy.com/rover-100-amp-mppt-solar-charge-controller/


Automatically detects 12V, 24V, 36V and 48V DC system voltages (for non-lithium batteries).
Compatible with various Deep Cycle battery options: AGM, Sealed, Gel, Flooded and Lithium.

That is a bit confusing...

I definitely understand how having the wrong charge controller may be affecting performance. But that wouldn't affect performance at the panels would it? When I take readings at the panels the amps still seem super low.

 

[John Frum]

That's super confusing. Haha. In the SCC settings it has an option for Lithium. So, that's what Ive set it to.

My battery have a 200a bms

We need to know the bulk/absorb and float voltages.
Lithium is a bunch of different chemistries.
It may think you have a battery with max voltage of 12.6 volts.
That would not charge your lfp battery very quickly at all.

Sure. What do you mean by Core?

batteries, inverter, solar charge controller and the busbars that tie it together.
Will probably ask for wire guages after I see the picture.

 

[John Frum]

I definitely understand how having the wrong charge controller may be affecting performance. But that wouldn't affect performance at the panels would it? When I take readings at the panels the amps still seem super low.

Yes it would.
The panels only supply what the charge controller pulls.

 

[McDubsy]

I'd start by separating out each string (of two panels), measure open circuit voltage and short circuit current.
Then connect each string one at a time to the controller to test output.

Also check the polarity. You could have one string or single panel. backwards.

Lastly, you're way over the spec sheet recommend max PV. If I read it right, max PV is 1300 watts. You've got double that!

Thanks for that advice! I will do those tests tomorrow.

My understanding about over paneling from talking with other members on this forum is that as long as I do not exceed the Max amps and voltage allowed by the charge controller I am okay.(200a and 150v)
I currently have the charge controller over panel in Watts but it is not over panel and amps and volts.

My Hope in doing this was to be able to produce more power in our dark winters.

 

[McDubsy]

Yes it would.
The panels only supply what the charge controller pulls.

Okay, I understand that.

If I separated a single panel and unhooked it and tested it with a multimeter at peak sun, should I expect to see around 40 volts and 10 amps as the sticker says?
I just did a test like that today and I am getting 40 volts and 2 amps. I have tested each of my eight panels in this manner and the results are identical.

 

[John Frum]

Okay, I understand that.

If I separated a single panel and unhooked it and tested it with a multimeter at peak sun, should I expect to see around 40 volts and 10 amps as the sticker says?

I don't think you have shared the sticker info from your panels.
But assuming the open circuit voltage is 40 volts you should see ~40 volts but 0 amps.
Unless you are using your meter in ampacity mode, is that what you are doing?

I just did a test like that today and I am getting 40 volts and 2 amps. I have tested each of my eight panels in this manner and the results are identical.

 

[400bird]

Something odd there.
40v @ 10 amps would make these 400 watt panels.

How did you measure the current when you did your amperage test on the panels today?