Pylon US3000C bank wrongly wired?

[Copernico]

I have a 3x US3000C battery bank with a 6kW Solis Inverter, installed by authorized professional in 2022 and it seemed to work. But, practically since the 1st day, my inverter kept sending Alarm messages all the time, often coupled with flashing LEDs and sounds from the batteries. The most frequent errors (among others now solved) were related to BMS. The most frequent flashing-LED-battery was the top one, followed at distance by the bottom one, sometimes all at the same time. The installer came back several times, but could never solve the BMS issue.

Today I noticed that the TOP battery with "linkport 0" empty, which behaves as the PRIMARY, receives the NEGATIVE WIRE FROM THE INVERTER. The bottom SLAVE battery has the POSITIVE WIRE FROM THE INVERTER connected. (Photo attached - dated today). This configuration is the opposite to all configurations I can see in the images online, including those on the Pylontech installation manual (4 bank photo attached). I could not find a printed specification about which battery should be connected to the direct plus and which to the direct minus.

I'd like to get your advice on this. I wonder:
- Is it true that my bank wiring configuration is wrong?
- Can it cause the frequent alarms?
- If yes, could running the batteries this way for over 1 year damage the batteries in any way?

I hope you can help me.

 

[jgh]

I'm pretty sure it doesn't matter, so long as pos and neg are at opposite ends of the stack.

 

[marionw]

The SOC lights do indicate that batteries are not balanced charge wise. Do you have the BatteryView.exe software so you can view each battery?
The installer should be able to provide you with this software (and the installer should also have this software) as well as the communications cable to connect the batteries to your computer.

If the installer did not FULLY charge all batteries (batteries are normally delivered at 40-50% SOC) then the installer should help you to get all batteries FULLY charged and all cells in each battery balanced. This is a process that should be done for each new battery added to an installation.

The positive and negative cables from the battery stack to the inverter are "crossed" to maximize equally pulling the same power from all batteries.

Also verify that the Inverter is correctly configured to use "CAN" vs "RS485" and that the correct communication protocol is selected.

With the correct communications cable (console port) MultisibControl (http://www.multisibcontrol.net) will also allow you to view the batteries and their charge status.

 

[rpdom]

I've got 2x US2000C on a Solis 3kW inverter. I can confirm that it doesn't matter which battery gets the pos feed and neg feed as long as they are at opposite end of the stack. This is to make sure the wire lengths are the same to each battery. It certainly isn't causing any alarms.

What are the alarms you are getting? I get occasional 2015 Alarm-BMS when one of the battery cells goes slightly over voltage when fully charged. New firmware in the batteries and inverter helped reduce the frequency of those. I used to get an average of one a day.