Volvo voltmeter volt source

[Karanga]

Volvo d2-50 motors (x2) , 1 Balmar 618 regulator, 1 alpha pro 3 regulator, 1 victron 712 display. 4 x 125 LFP batteries.

Where do the dashboard volvo voltmeters get their volt measurements from?

I occasionally get an overvoltage alarm when the motors are running and significant AC power demand (eg induction plate, watermaker etc).
But the Victron display (including Bluetooth data) says battery charging at 14.3 volts.

So what are the analog displays connected to, to be measuring a much different voltage?

PS: there are no separate start batteries, only house/start combo

[more]

Originally Posted by Karanga

Volvo d2-50 motors (x2) , 1 Balmar 618 regulator, 1 alpha pro 3 regulator, 1 victron 712 display. 4 x 125 LFP batteries.

Where do the dashboard volvo voltmeters get their volt measurements from?

I occasionally get an overvoltage alarm when the motors are running and significant AC power demand (eg induction plate, watermaker etc).
But the Victron display (including Bluetooth data) says battery charging at 14.3 volts.

So what are the analog displays connected to, to be measuring a much different voltage?

PS: there are no separate start batteries, only house/start combo

from your source of energy your installer of balmar regulator cut orginal vp energy source to Relay box with fuses, to main switch after this go to voltmeter.

[Karanga]

Originally Posted by more

from your source of energy your installer of balmar regulator cut orginal vp energy source to Relay box with fuses, to main switch after this go to voltmeter.

Thank you for your reply.
Unfortunately, I am having difficulty understanding it...

[wholybee]

More than likely the Volvo voltmeter is connected to the engine wiring harness, which probably is directly connected to the alternator output. In other words, not the battery. However the Balmar *IS* getting voltage sense from the battery. So, if a high load pulls down the voltage at the battery, the balmar is going to detect that, and increase alternator voltage to maintain the battery voltage. And the Victron is also connected to the battery voltage, so that is what it reads as well. Meanwhile, the Volvo meter is displaying the elevated Alternator output.

What size is the main Alternator cable to the battery, and how long is it? Likely, it is voltage drop in that cable that primarily accounts for the difference in voltage. Increasing it's size would help.