Modbus Registers for Ripple Voltage

Modifications
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1

I see in VRM that we are able to plot ripple voltage measurements from multis/quattros. This is great.

I see in dbus there is /Devices/0/Diagnostics/UBatRipple. This is great.

Are these ripple voltage values mapped to Modbus TCP registers (even undocumented ones)? Nothing for ripple shows up in the official Excel spreadsheet other than alarms.
Thanks.

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2

No, they are not.
But you can add them yourself.
Just be sure you pick a register value that has little chance to be later picked by Victron for other purposes.
For example, for my Multi RS, I’ve mapped it to 4690, as the Multi RS has values from 4500 to 4700 and the last one is at about 4620 now.

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3

Ok that’s easy enough, thanks!

4

For those following along later, I added the following two lines to
/opt/victronenergy/dbus-modbustcp/attributes.csv

Seems to work well for me.

com.victronenergy.vebus,/Devices/0/Diagnostics/UBatRipple,u,V DC,120,uint32,100,R
com.victronenergy.vebus,/Devices/1/Diagnostics/UBatRipple,u,V DC,122,uint32,100,R

Note that the update interval is 30 seconds (pretty slow).

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5

In my opinion it’s enough uint16 and for the resolution to millivolt, you need to set the multiplication to 1000.
But, nevertheless, it will work OK in the way you’ve done it, as long as it serves its purpose.

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