My VM III Twin 4K (Firmware 60.10) doesn’t read SOC accurately with RES-5WS LiFePO4. Help!"*

On 2025/07/19 at 8:00 AM, thamer said:

doesn’t read SOC accurately

Have you connected the BMS cable?

Is the battery icon flashing? It may take up to a minute from powering on.

Yes

On 2025/07/19 at 8:00 AM, thamer said:

RES-5WS LiFePO4.

I'm not familiar with that battery.

All I can suggest is later display firmware; that's what talks to the battery BMS.

What is your display/comms (U2) firmware version?

Please reply to my topic

All I can tell you is that I have no firmware, display or main, later than the ones you already have.

I have not had the time to study the BMS protocol part of display firmwares in any great detail.

On 2025/07/19 at 1:00 AM, thamer said:

My VM III Twin 4K (Firmware 60.10) doesn’t read SOC accurately with RES-5WS LiFePO4. Help!"*

How much is the difference between the battery and the inverter readings?

I think it is a calibration issue of volt reading. I have the same thing. My inverter reads 0.3 volts less than the battery, so the inverter application always shows 1% less SOC compared to the BMS.

On 8/9/2025 at 6:45 PM, AMalakani said:

My inverter reads 0.3 volts

could it be volt drop due to cable R ,