Currently I am having to reset the SOC display every couple of days. After a couple of days, it shows about 30% when in storage mode (54.4V), is there a specific method for calibrating this SOC reading so it doesn't need to be reset all the time?
Hi @Alexandra Found the issue, which was a dodgy battery (possibly internal BMS issue). I was discharging the batteries to see how long they would last and monitoring individual battery voltages, but after a couple of hours one of the batteries went down fast eventually dropping to 8.5V. The BMS is supposed to disconnect the battery at 10V but this also did not happen. I have disconnected the bank with the issue and the SOC meter now works correctly. :)
Hi @Alexandra I have change the battery setup to include the float level, however there is no way to disable the storage mode. I have simply set this to 54.4V the same as the recommended float value. The storage mode value cannot be set to 0V either as the lowest value available is 32V.
I have set the charge efficiency to 98% as per your recommendation with a Discharge Floor to 10% and will give this a try.
It would be nice to know what the calculation is that derives the SOC value so I could work out the expected setpoints. Thanks for your recommendations.
Hi @Alexandra I have finally been able to spend some time looking at this issue again. I have tried to calculate the Peukert Exponent for my batteries using a downloadable calculator. However the calculated value comes out at 0.5 which cannot be set using the app as it only allows 1.00 to 1.50 values. Not sure if I am doing this correct so I have the details below.
Also I am sure on the original firmware that the SOC meter would reset to 100% once Bulk Charging had completed. This does not seem to happen anymore so I am having to reset the SOC every day which is getting tedious.
The "Constant Current Discharge Characteristics" table shown is off the manufacturers spec sheet, I have not done any discharge testing of the batteries to verify this data and would not discharge to 10V anyway.
Since the ESS functionality relies on the SOC meter, I am keen to get this sorted. I will set the Peukert Exponent back to 1.00 (currently at 1.25), however I have had it at this value before but it still does not seem to work correctly.
@Alexandra I have now tried multiple combinations of all the "Battery Monitor" setpoints which still leaves me with the same issue. If I synchronize the battery SOC meter once the battery voltage is at FLOAT (54.4V) and during the night it discharges to the 40% ESS minimum discharge setpoint, the SOC meter does not increase from 40% when the batteries are charging no matter what combination of settings are used. The only way I can get the SOC meter to return to the preset charge efficiency factor is by re-synchronizing the meter again once the batteries have been charged.
Since the entire ESS functionality is dependent upon the SOC meter working correctly, this renders the ESS functionality useless. I would be happy at this stage to simply have the ESS SOC meter re-synchronize to the preset charge efficiency factor setpoint once charging has been completed. At least I can then modify the setpoints to provide the best linear discharge indication it will provide.
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