48v EG4 batteries reading very low amperage @ 42% SOC.

[Partimewages]

The shunt will measure accurately the amount of energy in and out of the pack. The BMS will accurately measure the individual pack cells for voltage.

 

[400bird]

So, are you saying the 3 eg4 batteries wired in parallel do not act and not seen as a whole energy source by the inverter?

As far as the load, yes the inverter just pulls in juice from anywhere it can get it. Communication is different.

I haven’t seen information that each battery has to be daisy chained with a comm cable and then connected to the inverter. Is this required? My understanding was the lead BMS communicates with the inverter to send the general battery system information for Voltage/amps/shorts/etc, it also monitors the voltage/amps/temp of cells etc for each individual battery. This discreet information temp/cells charge amt etc is not accessible from one battery to the next. That communication would have to be with some kind of battery monitoring software.

Right, sure. Each battery has a BMS to monitor it's own cells. They can also talk to each other and the inverter.
But you don't have communication cables plugged into batteries 2 and 3! So, the inverter only gets info from battery one and you aren't only seeing information on battery 1.

One would think that if a system is functioning fine prior with no heat/freezing/short events, one wouldn’t think something internal is happening with one or both of the rack batteries that are only 1.75 years old located in the house. This tack seems a bit contrary to what the folks at SS (Signature Solar) suggest.

Search the forum here for reports on the quality of support from SS.

All the voltage readings were within .1v. So in terms of what may be happening, does something come to mid?

Either something broke or there was an alarm on one of the batteries. Do you have any way to communicate with battery 2 or 3?

The direction from SS support was to independently charge the 2 rack batteries to within .2 volts of each other and re-assemble the battery array.

Excellent plan. When charging each battery individually, make sure to either disconnect or turn off the other 2.

The question I have now is; if the system works without a problem with the equalized batteries, what stops this unequal charging event with the current system configuration from happening again? Any idea?

Don't run with just one battery again? There really isn't enough info to know what happened. Next time maybe plug a laptop into the bottom batteries to check for faults?

 

[AndrewG]

Completely shut down your system and restart from scratch. turn off all breakers and disconnects. I recommend that you read and follow the inter and battery user manuals.

with the Inverter off
Turn on all battery breakers and battery disconnects. (Assuming the batteries are equally charged)
Next turn on the inverter.

What's the status of your inverter did it turn on and start supplying power?

Are you using battery communication?

A shunt at best, worst the calibrated BMS. Do you have the communication cable so you can read the bms data?

Do you mean a comm cable to plug into a computer?

 

[Zapper77]

Do you mean a comm cable to plug into a computer?

Yes, did you receive a usb plug wired to a rj45 connector.

 

[AndrewG]

As far as the load, yes the inverter just pulls in juice from anywhere it can get it. Communication is different.

Right, sure. Each battery has a BMS to monitor it's own cells. They can also talk to each other and the inverter.
But you don't have communication cables plugged into batteries 2 and 3! So, the inverter only gets info from battery one and you aren't only seeing information on battery 1.


Search the forum here for reports on the quality of support from SS.

Either something broke or there was an alarm on one of the batteries. Do you have any way to communicate with battery 2 or 3?

Excellent plan. When charging each battery individually, make sure to either disconnect or turn off the other 2.

Don't run with just one battery again? There really isn't enough info to know what happened. Next time maybe plug a laptop into the bottom batteries to check for faults?

Thank you for the insight/information. Think it’s time to step up to a battery system monitor since our farm is off-grid and in a very rural part of MT! We have to figure out so may systems, every time something goes haywire, we just have to figure it out bc there is very little local tech support for solar here. I do have the comm cables but not assessable now. Will likely have to buy new ones. Can you suggest a battery monitoring program?

Thanks,
Andrew

 

[Zapper77]

Can you suggest a battery monitoring program?

Thanks,
Andrew

EG4 has both programs that can read battery BMS, available for download.

Resources - EG4 Electronics

EG4 Electronics

eg4electronics.com

 

[Partimewages]

Victron Smartshunt
All Victron equipment is well supported and documented.

 

[740GLE]

Is this the first winter with this system?

This installation is in a climate controlled environment right? Say 60f at the lowest?

I fear winter solar production won’t be good for your loads.

 

[AndrewG]

T

EG4 has both programs that can read battery BMS, available for download.

Resources - EG4 Electronics

EG4 Electronics

eg4electronics.com

Thanks, I’ll do that!

you!

Is this the first winter with this system?

This installation is in a climate controlled environment right? Say 60f at the lowest?

I fear winter solar production won’t be good for your loads.

Not the first winter with the system. Batteries are in the house, Aware of EG4 batteries 30 degree BMS shut off. We do spend a fair amount of time sweeping/scraping snow off the panels. Our current issue was caused by 3-4 days of cloud cover & snow. Batteries drained down, apparently not equally, and some settings on Growatt Inverter caused issues with bringing them back up. Hopefully we have solved the problem by pulling each battery out of the series,
and charging them individually up to similar voltage, and then reassembling the array.

Fingers crossed, we re-assembled the system last night, the system was brought back up to full charge with a couple of hours of sun this morning. We are still dealing with some buggy issues with the inverter sending power to house load panel, but working thru this now. There are some settings on the Growatt we are learning about now that control charging voltage/priority,etc. Hopefully we have the settings corrected.
Thank you,
Andrew