I have two 11 kW hybrid inverters connected in parallel. My issue is that one of the inverters measures the battery group voltage as 52.8V, while the other measures it as 50.1V. How can I resolve this issue?I have two 11 kW hybrid inverters connected in parallel. My issue is that one of the inverters measures the battery group voltage as 52.8V, while the other measures it as 50.1V. How can I resolve this issue?

Also, the serial number of my device has changed.

(Old sn: 00202209008390 )

You will have to be very specific about your hardware ie: Type of inverters, batteries, panels etc

Then the clever guys will be able to help, give as much info about your hardware and setup as possible.

Inverter tommatech 11kw hybrit.

Battery: 2 x 280 ah lifepo4 of jk bms

panel: 18 x 575 wp tommatech

inverter firmware u1 573.78 

On 2025/01/07 at 11:48 PM, Macarxp said:

My issue is that one of the inverters measures the battery group voltage as 52.8V, while the other measures it as 50.1V. How can I resolve this issue?

22 hours ago, Macarxp said:

Also, the serial number of my device has changed.

The serial number as well as the calibration data are stored in EEPROM. Somehow, your EEPROM has become corrupted. I have no idea how this happens.

Ideally, to fix your serial number issue, you should get a setserial tool from whoever you bought the Tommatech inverters from. It's possible that 60 days runtime after the serial number was corrupted, that inverter could stop with fault code 90. If that happens, PM me and I'll send a re-patched version of patched firmware version 573.78.

In the meantime, you can fix the battery calibration by following the instructions here. The instructions are a bit old and confusing, post here if you have trouble. Note that with your model, as with most recent models, you will have to use the ATE1 command to send special commands straight through from the serial port to the inverter's DSP. These days, there doesn't seem to be an ATE0 command to undo it, so just reboot the inverter to go back to normal, or just unplug and re-plug the removable display.

Could you share the patched software with me? This situation has been bothering me, and I want to fix it as soon as possible. Also, could you share which programs are necessary for calibration? I would greatly appreciate it.

By the way, the status of the batteries is as follows.

Before this issue occurred, I experienced something unusual. While navigating through the inverter monitoring software on my computer, there was a sudden loud sound from the inverter, and it switched from battery mode to grid mode. It was a strong sound. When I checked the device, I noticed that the voltage dropped from 230V to 220V. Subsequently, the serial number changed, and a battery calibration issue arose.

Hello coulomb, I followed the battery calibration instructions, but all the commands returned a “NAK” error.

As per link, see below 

 

If you find that all BAT commands get NAK'd, it may be that your model (especially lower power models) use the PBAT command triple:

PSDF

PBATL1198

PBATH1401

16 hours ago, Macarxp said:

I followed the battery calibration instructions, but all the commands returned a “NAK” error.

Were you using the communications tool, or other means to generate CRCs for the commands?

Was your display in ATE1 mode? In this mode, the values (output voltage etc) don't update, I believe.

6 hours ago, Marius2001 said:

If you find that all BAT commands get NAK'd, it may be that your model (especially lower power models) use the PBAT command triple:

True, but 11 kW is hardly a low power model. Also, we know that the main firmware is 573.78, based on factory firmware version 73.78, which definitely implements the BTA series of commands.

I think there is a hardware issue with my device. The settings I apply are reset to factory defaults every time I turn it off and on. I’ve decided to send the device for warranty service. Thank you very much for your attention.

Hello everyone, I sent my device for warranty service. The issue was resolved with the service software. I had installed the same software myself, but the problem wasn’t fixed. I guess they use a different software at the service center. 

Hi @Macarxp,
I have absolutely the same setup of 2x11kW TommaTech Inverter in parallel and I face absolutely the same issue that 1 of Inverters (actually the Sleeve one) after each Restart (shutdown all Power supplies completely or Restart after Error with "Weak Battery" for instance) change its Serial Number and shows Lower Battery Voltage (also Lower: Grid Voltage, Output Voltage and Bus Voltage).

I restoring Original Serial Number and calibrating Battery after each Restart but this is not solution of course and I am looking also for proper/final solution.
I am afraid that this is hardware problem but not software one.

Edited January 27, 20251 yr by aamilev

6 hours ago, aamilev said:

I am looking also for proper/final solution.

I think that you need to replace the control board. Unfortunately, this will have default calibrations for everything, But at least it should save the serial number and battery voltage calibration values.

The EEPROMs are a critical part of the Voltronic inverters, and a lot of them seem to be failing lately.

On 2025/01/27 at 3:32 PM, Coulomb said:

I think that you need to replace the control board. Unfortunately, this will have default calibrations for everything, But at least it should save the serial number and battery voltage calibration values.

The EEPROMs are a critical part of the Voltronic inverters, and a lot of them seem to be failing lately.

Thank You very much for advice.
Unfortunately, I have no idea from where to take spare Control board.