What this module provides
The 6AG1138-4DF11-7AB0 is a SIPLUS variant of the ET 200S EM 1SI serial interface module, based on 6ES7138-4DF11-0AB0 with a conformal coating for harsh environments. It adds one serial channel supporting RS-232, RS-422, or RS-485 with selectable protocols: USS for drive communication or Modbus RTU for PLC-to-device links. Baud rates from 110 to 115.2 kbit/s, half duplex. Power draw is typical 20 mA from the 24 V DC supply (max. 80 mA) plus 10 mA from the backplane bus, with a typical power loss of 1.2 W. Operating temperature range is -25 °C to +70 °C, with derating at higher altitudes per the pressure-altitude table. The conformal coating and resistance to aggressive gases, salt spray, and oil make it suitable for harsh environments.
Integration notes
Physical width is 15 mm, same as standard ET 200S electronic modules. Depth 52 mm, height 81 mm. A single interface port is available, selectable for RS-232 (full 8-signal DTE with TxD, RxD, RTS, CTS, DTR, DSR, DCD, PE), RS-422 (TxD/RxD with GND), or RS-485 (half-duplex R/T with GND).