New PV+Batteries system underperforming

[aluis]

So the drama continues!

Yesterday the inverter sent an alarm notification "Grid Lost (energy storage)" and shut down. It's still not working today.

First the installer said it was overvoltage of the grid of (252v). I checked the logs and the previous day the grid had an overvoltage of 256v and 257v and it didn't cause a shutdown. So this can't be the issue.

Today the inverter still hasn't recovered and is obviously not producing energy, and the battery is also not discharging. The installer says it's due to the bad weather, when it's obviously not the case. He said he;d investigate further and I'm waiting. Besides of the obvious clueless installer, I'm trying to understand myself what could cause this to occur and why, 24 hours later the inverter is still shut down.

I don;t know what to do and would be very grateful for any advice.

[solardreamer]

This is the inverter manual. I can only find a setting to set the country but nothing regarding grid parameters. Do all inverters contain that?

https://img.saj-electric.com/file/H1-3~6K-S2%20User%20manual-20230328065532946.pdf

I doubt I'll be able to reach anyone technical to discuss grid voltage with my energy provider but I'll try if all else fails and appreciate the suggestion.

The inverter has RS485 port so there maybe management software available for it to configure grid settings. I suggest you contact the manufacturer for more info and support.

[aluis]

Not sure how things work in Portugal but the inverter should have configurable grid settings if it sold for use in different regions/countries that can be changed to allow higher but still voltage. Assuming you bought the inverter from the installer, you should ask the installer about it. if the voltage is really outside the valid range for your grid then then you should contact your power company to adjust.

This is the inverter manual. I can only find a setting to set the country but nothing regarding grid parameters. Do all inverters contain that?

https://img.saj-electric.com/file/H1-3~6K-S2%20User%20manual-20230328065532946.pdf

I doubt I'll be able to reach anyone technical to discuss grid voltage with my energy provider but I'll try if all else fails and appreciate the suggestion.

[solardreamer]

Not sure how things work in Portugal but the inverter should have configurable grid settings if it sold for use in different regions/countries that can be changed to allow higher but still voltage. Assuming you bought the inverter from the installer, you should ask the installer about it. if the voltage is really outside the valid range for your grid then then you should contact your power company to adjust.

[aluis]

I don't think you said where you are located.

Australian example: "The grid voltage Australian standard AS 60038 is 230V +10% -6%, which is a range of 216V to 253V. The Australian standard for your inverter instructs that it must disconnect from the grid if voltage exceeds 255V for 10 minutes or exceeds 260V for any amount of time."

Try to search for your country grid's requirements. What specs are used?

Manuals and information on the internet regarding your inverter & battery's troubleshooting information are sparse.

Battery #2 should have DIP switches set different than battery #1. I have to assume your installer knows how to make and crimp communication cables correctly.

Good luck!

Thanks, I appreciate the info.

I am in Portugal. I'm not sure of the exact specs of the grid voltage but it's definitely in the 200s. The installer said the inverter cutoff because it detected a grid voltage of 250, whic is too high. I have the inverter's manual which doesn't seem to contain parameters to set these limits. I guess these can't be set as they must be within the grids requirements.

Does this mean that I have to live with regular solar and battery cutoffs?

I also saw the DIP switches in the manual, when the second battery first didn't work, which I sent the installer. He just ignored me. He's probably fed up of my suggestions. I'm very disappointed with my choice of installer but too late to change now. And I'm not sure how to approach this without the communication deteriorating further. I still haven't paid for half of the costs. I'm holding on until everything is as up and running as possible. So I appreciate the feedback as I'm not aware of what he can or can't do about the cutting off issues.

Thank you.

[oregon_phil]

I confirmed and the strings were indeed split into 6 panels each.

The panels are now producing to full capacity but the problems don't end here.

The second battery was this morning all of the sudden recognized by the system, without any input from the installer. It's great that they now work but I would like to understand how it is possible that the system corrected itself.

The only problem remaining now is that the inverter is throwing 2 errors every couple of hours. They are "Grid Voltage 10 min. Average Overvoltage (energy storage)" and "Battery Open Circuit Warning".

When these are triggered the PV output is shut off and energy from the grid is used instead. After half an hour or so it goes back to producing solar.

The installer is blaming the unstable grid current that's triggering this. Is this true? I find it weird that the grid could shut down my solar production!

I don't think you said where you are located.

Australian example: "The grid voltage Australian standard AS 60038 is 230V +10% -6%, which is a range of 216V to 253V. The Australian standard for your inverter instructs that it must disconnect from the grid if voltage exceeds 255V for 10 minutes or exceeds 260V for any amount of time."

Try to search for your country grid's requirements. What specs are used?

Manuals and information on the internet regarding your inverter & battery's troubleshooting information are sparse.

Battery #2 should have DIP switches set different than battery #1. I have to assume your installer knows how to make and crimp communication cables correctly.

Good luck!

[SunEagle]

I confirmed and the strings were indeed split into 6 panels each.

The panels are now producing to full capacity but the problems don't end here.

The second battery was this morning all of the sudden recognized by the system, without any input from the installer. It's great that they now work but I would like to understand how it is possible that the system corrected itself.

The only problem remaining now is that the inverter is throwing 2 errors every couple of hours. They are "Grid Voltage 10 min. Average Overvoltage (energy storage)" and "Battery Open Circuit Warning".

When these are triggered the PV output is shut off and energy from the grid is used instead. After half an hour or so it goes back to producing solar.

The installer is blaming the unstable grid current that's triggering this. Is this true? I find it weird that the grid could shut down my solar production!

If your inverter has software that looks at the grid power and does not like what it sees it will turn off for a period of time. The issues could be voltage or frequency from the grid that falls outside the programmed parameters in the inverter. So yes the grid could be causing your inverter to stop.

You might have to contact your POCO and see what is happening on the grid and then your installer to see if the program in the inverter can be loosened up a little.

[aluis]

One would assume the installer is making two strings of 6 but don't assume anything. Inverter has a start voltage of 120 vdc which would be a string of 3 or 4 panels depending on Voc. Just ask the installer what's going on.

I confirmed and the strings were indeed split into 6 panels each.

The panels are now producing to full capacity but the problems don't end here.

The second battery was this morning all of the sudden recognized by the system, without any input from the installer. It's great that they now work but I would like to understand how it is possible that the system corrected itself.

The only problem remaining now is that the inverter is throwing 2 errors every couple of hours. They are "Grid Voltage 10 min. Average Overvoltage (energy storage)" and "Battery Open Circuit Warning".

When these are triggered the PV output is shut off and energy from the grid is used instead. After half an hour or so it goes back to producing solar.

The installer is blaming the unstable grid current that's triggering this. Is this true? I find it weird that the grid could shut down my solar production!

[solardreamer]

I believe you're right. The installer is laying more cable from the roof down as I type, to create a second string. Shouldn't this have been done first time around?

Are you talking about the same installer that didn't make sure the batteries were working fully before leaving? If so, I think you know the root problem cause.

[oregon_phil]

One would assume the installer is making two strings of 6 but don't assume anything. Inverter has a start voltage of 120 vdc which would be a string of 3 or 4 panels depending on Voc. Just ask the installer what's going on.

[aluis]

Does the inverter show any errors? The PV string voltage may be too high.

I believe you're right. The installer is laying more cable from the roof down as I type, to create a second string. Shouldn't this have been done first time around?

[oregon_phil]

I agree. Inverter max voltage 600Vdc, MPPT range 90 to 550VDC.

OP didn't panel specifics but guess 455 watt panel with half cut cells, Voc ~50 VDC = 600 VDC string voltage and maybe higher due to temperature coefficient depending on location.

Panels with lower Voc might be OK.

Disclaimer, I am not an installer.

[solardreamer]

Does the inverter show any errors? The PV string voltage may be too high.

[aluis]

How many panels do you have, what kind are they and are they arranged in two strings connected to the two MPPT inputs? Do you have any shadows on the panels?

No shadows at all. There are 12 x 455w monocrystaline panels. I believe they're all in the same string.

[oregon_phil]

How many panels do you have, what kind are they and are they arranged in two strings connected to the two MPPT inputs? Do you have any shadows on the panels?