bschack avatar image
bschack asked

BMV-700 history item "J SYNCHRONIZATIONS" stuck at 0

I have a BMV-700 hooked to a 12V lead-acid battery, powered by 2 Blue Solar MPPT 75/15 controllers. The BMV is hooked up correctly - it shows proper voltages, power, current (with the correct sign), ... - but the history item, "J SYNCHRONIZATIONS" is stuck at 0. I assume that when the BMV encounters the correct conditions to perform an auto-synchronization, it should increment this counter. Am I mistaken?

Here are the relevant BMV parameters I've changed (the rest are left at default values):

01 Battery capacity - 242Ah

02 Charged voltage - 14.4V (the charger controllers are set to 14.7V absorption voltage)

Now, I've watched the monitor, and I know that the battery has exceeded 14.4V for more than 3 minutes with a current of less than 9.7A, so it should have automatically synchronized. The battery icon is not flashing (I have done some manual synchronizations). Any idea what's going on?

BMV Battery Monitor
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boekel avatar image boekel ♦ commented ·

what have you set for 'tail current' and 'charged detection time'?

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bschack avatar image bschack boekel ♦ commented ·

They're both set to their default values: 4% for tail current and 3 minutes for charged detection time.

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1 Answer
Paul B avatar image
Paul B answered ·

was the SOC already at 100% as a sync may only occur if the SOC is not at 100% when the batteries are charged.

just a thought thats all

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bschack avatar image bschack commented ·

That's quite possible (I'll confirm it the next time the sun fully charges the batteries). So is that how the monitor works - it only does an automatic synchronization *if* the parameters are satisfied *and* the SOC isn't already 100%?

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