question

rongicz avatar image

Modbus TCP - different devices, same Unit ID

Hello,


I have upgraded my system from SmartSolar 250/70-Tr VE.Can to latest SmartSolar RS 450/100-Tr (with latest firmware), but now I have a problem with Modbus TCP because SmartSolar RS now has same Unit ID as installed SmartShunt (both 238). Old MPPT has Unit ID 239 and everything Modbus TCP related was fine.

Installed Venus OS version is latest v2.65~8.

Both devices are connected via VE.Direct-USB to different USB ports.

Is any possibility to change it somehow ? Because now I can`t read Modbus registers correctly.

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Venus OSmppt smart solarModbus TCPsmart shunt
1616846254112.png (36.1 KiB)
1616846277416.png (52.4 KiB)
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2 Answers
mvader (Victron Energy) avatar image
mvader (Victron Energy) answered ·

I’m quite sure its no problem they have the same unitid: the registers don’t overlap

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rongicz avatar image
rongicz answered ·

You are right, sorry... I was confused, because it is currently (probably) not possible to read PV voltage and current (address 776 and 777)... because of multiple MPPT trackers ? PV power (on 789) is OK... Are you planning to add these trackers to ModBus TCP registers ? Thanks !

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