ABB RELION REX640 - 3.2.10 Physical locations of the serial channels

3.2.9 Assigning of a serial communication protocol to a COM
serial port
The settings of the serial communication protocol instance include a setting
parameter, called either Port or Serial port , which is used to select the COM1 or
COM2 setting.
Since not all serial protocol standards allow changes in link parameters,
all link setting parameters are not found in the COMn settings. Additional
link setting parameters are found in the setting parameter list of the
used serial protocol.
3.2.10 Physical locations of the serial channels
The physical location of the COM1 and COM2 drivers depends on the link mode
used which, in turn, depends on the used communication hardware option. Serial
channels can be found on communication boards COM1004...COM1005.
• X7 is the fiber-optic interface. Only driver COM2 can be configured into fiber-
optic mode.
• X8 is the RS-485/IRIG-B interface. Both drivers COM1 and COM2 can be
configured to this interface: COM1 and COM2 can act as two RS-485 2-wire links
or, alternatively, COM1 can act as one single RS-485 4-wire link. Both ports are
galvanically isolated serial communication ports.
Table 38: Connector X8 signals
Pin No Pin name Description Alternative
1 GND EARTH
2 GNDC GND connected to
earth via 1nF capaci-
tor
3 NC
4 IRIG-B - ISOL2_GND
5 IRIG-B +
6 ISOL_GND RS485 GND
7 RS485 B1/- 2-wire - , COM1 4-wire TX pair, COM1
8 RS485 A1/+ 2-wire + , COM1 4-wire TX pair, COM1
9 RS485 B2/- 2-wire - , COM2 4-wire RX pair, COM1
10 RS485 A2/+ 2-wire + , COM2 4-wire RX pair, COM1
1MRS759142 F Basic functions
REX640
Technical Manual
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