Change ESS grid setpoint from remote

DIY
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1

I am running ESS on a Multi RS Solar. Is it possible to change the grid setpoint from custom software on another computer. With the Multiplus II I used Modbus TCP which worked great. But I cannot find a way to do it with the Multi RS,

Thanks in advance.

2

Try register 4610 or 4922 on Modbus for Multi RS ID (usually 100, the same as the system).
Be careful that they are 32 bit registers.

1 Like
3

These registers return 0 while I have entered another value in VictronConnect (ESS → Grid setpoint).

4

When I change the setpoint via Node Red, it succeeds. But after a short time, within a minute it changes back to the original value. It looks like the ESS grid setpoint cannot be controlled like it used to be.

The mode of the Multi shows “External Control”, while I selected “Optimized without battery life” in VictronConnect. This could explain why the setpoint changes back.

5

I wrote to both registers via ModbusTCP. They act similar. The setpoint is changed, but falls back after exactly an minute. The setpoint is not visible in VictronConnect.

If the setpoint is resent within a minute, the the period is extended. So I think about creating a Node Red flow that rewrites the current value of the register every 45s or so. Then the behaviour is as expected.

6

Yes, that worked. I created a small flow that keeps the setpoint in the register.

afbeelding
afbeelding734Ă—109 5.62 KB

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