Device Compatibility Please update your inverter to the latest firmware version to enable modbusTCP, this is supported from v144 onwards.
| Device Type | Variants | Modbus TCP (Ethernet) | RS485 | Curtailment |
|---|---|---|---|---|
| Venus-C | 2.5kWh | ✅ | ✅ | ❌ |
| Venus-E | 5.1kWh |
Device Compatibility This integration was tested with Venus C device. However, other devices using the same communication protocol, such as Venus E, may also be compatible. If you have such a device, it is likely to work, but we are awaiting official confirmation from the manufacturer.
For the configuration of the device, please follow the guide: Marstek official guide
The Sofar EMS and the Marstek inverters communicate via RS485. From the V3 version of Marstek, there is native Modbus TCP support that can be used to connect directly through the LAN cable.
The RS485 port can be found in the following diagram and the cabling is depending on the version of the device.
The A and B cables are different for V2 and V3. Below you can see the connection for V2.
For V3 the cables 1 and 2 represent B and A respectively, while cables 4-5 are connecting to VCC amd 7-8 to GND. Once connected, the cable will be as such:
| Device | Sofar EMS model OM1 | Sofar EMS model IG8 | RS485-USB converter | RS485-Ethernet converter |
|---|---|---|---|---|
| A | RS485 A | RS485_POS | RS485 A | TX+ |
| B | RS485 B | RS485_NEG | RS485 B | TX- |
| GND | RS GND | GND | Not available | G |