I have connected the power of a Venus GX on a service battery and also a multiplus. Now I see on the VRM Website (monitor) a voltage of 9.6 Volt but my service battery has 12.5 Volt. Why is there a difference between the VRM monitor and the real voltage of the service battery?
On the Multiplus battery wires connectors the same as on the battery at this moment 12.55 Volt.
In Venus GX, if you go to "Settings" and then "System Setup", what you have set for "Battery monitor"?
And do you have DVCC enabled?
You only have the Multiplus and Venus GX, right?
What kind of battery do you have? Lead-acid, LiFePO4 (and if yes, what BMS, if any)?
Edit
Also list the Venus GX and Multiplus firmware versions.
Yes only Multiplus 12/3000/120 and Venus GX with GSM and GPS.
AGM battery no BMS at this moment.
I have a BMV 712 but not connected yet.
The Multiplus firmware version can be seen via VRM, in Device List (VE Bus System).
You can see the Venus GX firmware version in the menu, or via VRM (Gateway).
Multiplus firmware version is 158 product-ID 2609
Venus GX version v2.63
Venus GX firmware is the latest, but Multiplus firmware is very old.
You can't activate DVCC with that old firmware version on the Multiplus.
In order to update the Multiplus firmware, you need a MK3-USB interface.
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Still, change the "Battery monitor" (in Venus GX) from Automatic to Multiplus. This setting is used for SOC, so it might have no effect for voltage, but it is easy to test. Not sure what Automatic mode is using.
After you install the BMV, make sure you set "Battery monitor" to it.
Thank you for now I will try with BMV 712 and newer firmware.
I have tried VictronConnect but did not work.
Now I will use VEFlash which firmware should I use at this moment the Multiplus is product-id 2609 en version 158 reading out with the Venus GX.
I have tried VictronConnect but did not work.
Can you give more details?
The latest firmware is 481 (so 2609481.vff for your Multiplus).
Software VictronConnect gives the answer:
Firmware-versie wordt niet ondersteund. Gebruik VEFlash om te updaten naar versie 200 of hoger.
The current FW is to old for VictronConnect, so you have to use VEflash.
After firmware upgrade to 2609481 and connecting BMV monitor on the Venus GX everything works very nice.
