dayandnight avatar image
dayandnight asked

Modbus Multiplus-II GX - Relay seting

Hello Vicronauts,

I am trying to go some more deep in MODBUS communication. I going to adapt my wallbox based on a Siemens LOGO! controller to use maximum solar energy which is actual produced in combination if neccessary with using the batteries but not using GRID support.

I was successfully to read based on the Victron spreadshead the registers all necessary values and use them to do the job on the LOGO!. But now I need to switch by the LOGO! controller one relay in my 3-phase Multiplus-II setup thru modbus.

I tried it with register 806 and +/-1 as well with 805 and 807 but it didn't work. I am wondering if I use the right register? My GX-device is integrated into the Multiplus-II. Therefore I think the relay I can connect to on the Multiplus-II is different from a CCGX Relay? Isn't it?

In the spreadsheet there can be found following relays.

  • 806 - com.victronenergy.system - CCGX Relay 1 state
  • 280 - com.victronenergy.battery - relay status
  • 780 - com.victronenergy.solarcharger - relay on the charger
  • 2320- com.victronenergy.charger - relay on the charger

But not one of them looks to me as suitable to use for my intention!

My fundamental question is it possible to access the relay on a Multiplus-II GX thru MODBUS?

And in detail, how to address a relay of a specific Multiplus-II? I use three of them in a 3-phase installation.

How about the "open collector outputs" K1 and K2 of the three Multiplus-II?

Perhaps there is only a way in a combination with a assistant? Relay assistant? But I couldn't puzzled it out! I would appreciate very much any input on this, which puts me onto the right track! Thanks in advance


Modbus TCPRelay
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2 Answers
wkirby avatar image
wkirby answered ·

The MultiPlus relays (aka VE.Bus relays) are not available via MODBUS. As you have summised, there are no registers for them. There are no registers for the open collector outputs either.
There are no assistant configurations that would create an accessible register for these.
Built-in Venus devices such as MultiPlus GX do not have relays.

Basically, with your setup, there are no relays available over MODBUS.

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dayandnight avatar image dayandnight commented ·

Hello @WKirby,

I was afraid to get this answer. ;-) I have to do it in another way. Thank you for your quick response.


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dom avatar image
dom answered ·

Bonjour, j'essaie aussi de connecter mon logo sur un Color Control par modbus. Je n'y arrive pas. pouvez-vous me donner le bloc fonction qui le souhaitei (ou la procédure :))

Merci encore

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Modbus TCP Basics

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