Charging Fluctuations

[torrmundi]

Towards the end of the absorbtion phase of charging my AGMs (>90 SOC), the voltage is fluctuating rapidly in the range of 14.3-14.5 volts and the current is also fluctuating rapidly in the range of 25-50A, before finally going way down to 1-10A. Why the fluctuations? Is it a normal artifact of the charging algorithm?


My charger is Magnum's Magnasine Hybrid pure sine wave charger/inverter, MSH3012. My batteries are Lifeline GPL-4DL (3x 210Ah)

[torrmundi]

Magnum said:
"For the voltage to rise the resistance must be lower so amperage goes up and then the vdc.
Probably a battery issue; you can look at connections and possibly the battery temp sensor. If temp sensor had a resistance issue and jumping around it would tell our charger to raise vdc then lower, if temps dropped.

First thing would be to check the BTS (Battery Temp Sensor) by pressing the “TECH” button and selecting 01 Temperatures and checking the BTS temperature.
If that checks out then most likely a battery/battery connection issue."


BTS shows 73F, thermocouple/voltmeter reads 64F, 2nd thermocouple/voltmeter reads 60F, Victron battery sense shows 73F.