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Setup guides → KOSTAL
KOSTAL
Sunplug reads KOSTAL on your own network through the Sunplug Agent, over the inverter's SunSpec Modbus profile. No account, no cloud, no subscription.
This was tested against the vendor specifications but isn't running for Sunplug customers yet. If you experience any issue setting it up, reach out to [email protected] and I will work with you to iron out any issue.
Which KOSTAL inverters
PLENTICORE and PIKO IQ — the generations that publish SunSpec over Modbus TCP.
Setting it up
- In the inverter's web interface, enable Modbus TCP. Keep the defaults: port 1502, unit id 71
- Install the Sunplug Agent on an always-on device on the same network as the inverter
- The agent finds the inverter and identifies it as a KOSTAL
Leave the byte-order setting alone. The little-endian / big-endian option only affects float registers, which Sunplug does not read. Changing it will not help and may break other software.
You need the Smart Energy Meter for surplus
Without a KOSTAL Smart Energy Meter you get production only, not house consumption. Fit one, or add a Shelly at your supply point.
The battery is not read yet
On a KOSTAL hybrid the battery shows as absent; production and grid are read. Charging works, just not battery-aware yet. It is on the list.
When it does not work
The agent finds nothing
Modbus is off from the factory: switch it on in the inverter's interface. Check the agent is on the same network as the inverter.
Consumption is missing
The Smart Energy Meter is missing or not commissioned. If the inverter's own display shows no household consumption, Sunplug cannot see it either.
The battery does not appear
Expected for now — see above. Nothing else is affected.
Stuck? Email me with the model and whether a Smart Energy Meter is fitted.