Does anyone here know how a Torqeedo Cruise 4.0R measures battery pack voltage? I ask because I added a Victron BMV712 monitor to my system and its volt meter does not agree with the Torqeedo’s volt meter. When almost no current is being drawn from the battery pack, the Torqeedo reads approximately 0.4 volts more than the Victron. (For example, when not in motion, the Torqeedo console says 53.6 V while the Victron says 53.22 V. The LiFePO4 pack is about 85% full). I then noticed that when underway using about 1200 watts, the Torqeedo voltage drops faster that the Victron’s. At higher currents, the two voltages approach each other. Any ideas why? I got out my Fluke 87 multimeter and it agrees with the Victron. Of course, the Victron’s shunt would lower the voltage to the motor when underway, but it certainly doesn’t account for 4 tenths of a volts. 25 amps through the shunt should only account for a 2.5 millivolt drop. I can imagine the Torqeedo measurement is just off by 0.4 volts, but why would it improve accuracy when underway?
Note that this situation isn’t causing any problems. I’m just curious.
Pat
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