IEM 2100 Series | Sofar EMS Documentation

Supported Devices

The IEM 2100 Series are single-phase energy meters.

Device Type	Modbus TCP (Ethernet)	RS485
Schneider-Electric iEM 2100 Series	❌	✅
Schneider-Electric iEM 2150
Schneider-Electric iEM 2155

The IEM 2100 series communicates via Modbus RTU over RS485.

For correct RS485 wiring: follow the RS485 wiring guidelines.
If the wiring shown in the table below is incorrect, please let us know.
There is no general industry consensus on the use of A and B for RS485 polarity, so the naming may be counterintuitive for some devices.

Device	Sofar EMS model OM1	Sofar EMS model IG8	RS485-USB converter	RS485-Ethernet converter
D1 (+)	RS485 A	RS485_POS	RS485 A	TX+
D0 (-)	RS485 B	RS485_NEG	RS485 B	TX-
0V / Shield	RS GND	GND	Not available	G

Please refer to the device manual for the exact pin locations, as they may vary slightly between specific sub-models (e.g., iEM2150 vs iEM2155).

You MUST give each device a unique address on the RS485 bus. Check the device manual for instructions.
Use lower addresses first (1, 2, ...) because the Sofar EMS will find them faster!
For each device, it is generally recommended to keep the factory-default baud rate, parity, and stop bits. The Sofar EMS will scan those first.

Ensure the device settings match the driver capabilities defined below:

Check the device manual on how to enter the energy meter's configuration menu to set the Modbus Address and Baud Rate.

Last updated August 24, 2026