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apple047 avatar image
apple047 asked

Duplicate Modbus ID

38f59b22-1635-4d9d-909c-8ca5b4247604.pngHello,

I recently started to map the Modbus signals in home assistant and noticed the Modbus IDs for grid meter and PV inverter meter are the same, on other installations I found them to be different, I would have expected them to be different as to not cause conflicts, is this normal? Would this cause issues in data flow?

Can the Modbus IDs changed at will?

Thanks George


Modbus TCP
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2 Answers
pau1phi11ips avatar image
pau1phi11ips answered ·

I think this will be the same meter. It's just the old entry before you changed the meter assignment to PV inverter instead of the default Grid meter. I wonder if rebooting will remove the duplicate.

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apple047 avatar image apple047 commented ·

Sorry I haven’t mentioned in the description, these are 2 independent meters connected to the installation, functionality of the installation is not being affected so far but I wonder if communication will…

I’ve tried rebooting, disabling and enabling Modbus services with no changes


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Ingo avatar image Ingo apple047 commented ·
Looks like a Modbus addressing bug then, sorry 'undocumented feature'. Or I might be wrong. The big guns must chip in here.
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Ingo avatar image Ingo apple047 commented ·
Try removing the PV's Grid Meter USB plug and delete it from devices with a reboot. Once gone, plug it into a different USB port and see if a new ID comes up.
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apple047 avatar image apple047 Ingo commented ·

I haven’t tried this combination, will give it a go once on site

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apple047 avatar image apple047 Ingo commented ·
Hi,

Just to update, I’ve disconnected both meters and deleted them from the system but when connected back the GX card assigned the with the same Modbus ID, strange behaviour, maybe Victron can shine some light if possible please.

Regards George

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Ingo avatar image Ingo apple047 commented ·
Just for interest, on your other installations, are the two id's between 30 and 34? If so then just for kicks try a modbus query on the other id's (30/31/33 and 34) to see if any of the other returns valid data.
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Sébastien Oggier avatar image
Sébastien Oggier answered ·

Hello.I've the same problem, the Smart Shunt Unit ID is 228, should be 229 (like on my 3 anothers devices). 1720274258090.pngAny Idea to solve it?


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Related Resources

Modbus TCP Basics