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smarsystemsluke avatar image
smarsystemsluke asked

How to find Unit ID for Device Instance that ins't in the ModbusTCP excel sheet?

I have an OctoGX gateway connected to 9 SmartSolar Charger MPPTs. For all but 2 of the Chargers I can find the Unit ID according to the Device Instance using the 'CCGX-Modbus-TCP-register-list-2.31', but two of the chargers have Device Instance 295 and 296 which aren't lister in the spreadsheet.


Is there a way to find the Unit ID of these two so that I can connect to them over ModbusTCP like the others?

MPPT ControllersCCGX Color ControlModbus TCPgx device
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3 Answers
smarsystemsluke avatar image
smarsystemsluke answered ·

The Unit ID mapping for Device Instances 294 - 296 were added to the file '/opt/victronenergy/dbus-modbustcp/unitid2di.csv' by opening an ssh console to the gateway (logged in as root) and manually adding the additional lines to the csv, and then rebooting.

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Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

There is also a new feature in the upcoming Venus v2.40 to show UnitID's.

alt text


modbus-ccgx.png (231.9 KiB)
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Pieter Boomsma avatar image Pieter Boomsma commented ·
it would be helpfull if this also shows the serial number or the name of the device. I got quite some of the same MPPT's in 1 system now, i was however able to find out but its a bit of a pain in the .. :)
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richoff avatar image
richoff answered ·

screen-shot-2022-05-03-at-71630-am.pngI have 3 unit ID's of "100"... doesn't seem right.


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Related Resources

Modbus TCP Basics

CCGX Product Manual

CCGX Product page

MPPT Product Page

MPPT Error codes

MPPT 150/60 up to 250/70 Manual

Additional resources still need to be added for this topic