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gordon-waldmann avatar image
gordon-waldmann asked

Does AC ripple affect %SOC readings on BMV 701

My BMV 701, connected to the same shunt as my coulomb meter, with the same calibration and battery Ah settings, shows over estimate of discharge Ah and underestimates of recharge Ah. Is it possible the 100Hz AC ripple from my inverter charger is affecting the measurements?

BMV Battery Monitor
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2 Answers
Alexandra avatar image
Alexandra answered ·

@Gordon Waldmann Can you measure an AC voltage over the DC cables using your Multi-meter? When an AC voltage is present on DC cables it is called DC ripple. Usually present because of bad crimps, undersized cabling or two many switches and shunts in the DC system.

I am assuming that is why you used one shunt for two devices. I would also wonder if the BMV is only designed to work with its own shunt, since not all shunts are the same? On this I am speculating as I have never tried it to be honest.

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Daniël Boekel (Victron Energy Staff) avatar image
Daniël Boekel (Victron Energy Staff) answered ·

Hi @Gordon Waldmann

What is the Peukert factor set at? this probably makes the difference.

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