N-Tron ESERV-M12T, User Manual

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Setup and Connections ESERV-M12T Modbus Gateway
9 ESERV-M12T (Rev. 1210)
When configured for 4-wire operation the connection supports two signal pairs: RXA(-), RXB(+) and TXA(-), TXA(+),
plus GND. This makes full-duplex operation possible. The data lines are differential pairs (A & B) in which the B line
is positive relative to the A line in the idle (mark) state. Ground provides a common mode reference.
When configured for 2-wire operation the connection supports one signal pair: DataB(+) and DataA(-) signal
channels using half-duplex operation. The data lines are differential with the Data B line positive relative to Data A
in the idle (mark) state. Ground provides a common mode reference.
CONNECTING THE ESERV-M12T
The ESERV-M12T has two serial connections that support RS-232, RS-422 and RS-485 (2- and 4-wire). The unit has
two connectors, both of which are 5-position terminal blocks. Make the appropriate connections to the terminal
blocks to match the serial connection mode you select when configuring the Modbus gateway.
Note: Refer to Appendix D for connector pin out information.
Figure 11. ESERV-M12T Connections