EM920 – Modbus Master Functionality. Ethernet to serial routing.


Supported in firmware version 28.XX.11 and higher.

Setting of new features is supported in PAS 1.4.11 or newer.


1. Should be installed termination resistor 120 Ohm between RS485 ‘+’ and RS485 ‘-‘ COM3 or COM4 of EM920.

2. On the MeterSetup/Communication Setup/Network Setup tab, setup the master device address for the Internet application protocols.

The meter will only respond to this address after the routing table is configured.

  • Default Device Address is ‘1’.


3. On the MeterSetup/Communication Setup/Serial Ports tab, select a serial port (COM3/COM4) you wish to use as a client/master port and set it to Client/Master mode.

Setup the protocol, baudrate and data format for communicating with the slave meters.

Higher baud rates are recommended. Adjust the receive timeout for the port if required.

4. On the MeterSetup/Communication Setup/Gateway Routing Table tab,

select a master destination port and type in the meter routing address on the serial network to which messages are to be forwarded.

The slave addresses must be differ from the master device address.


5. Communicating to slave devices via the EM920 master device.

Set Device Address in PAS as it defined in Gateway Routing Table (step 3).


Note: USB port of EM920 doesn’t support Modbus master’s functionality.