ProSoft Technology MVI94-MCM-MHI - Manual (Page 71)

MVI94-MCM ♦ Flex I/O Platform Reference
Serial Communications Modbus Communication Module User Manual
ProSoft Technology, Inc. Page 71 of 109
March 29, 2011
5.2.4 RS-422
The RS-422 interface requires a single four or five wire cable. The Common
connection is optional, depending on the RS-422 network devices used. The
cable required for this interface is shown below:
RS-485 and RS-422 Tip
If communication in the RS-422 or RS-485 mode does not work at first, despite
all attempts, try switching termination polarities. Some manufacturers interpret +
and -, or A and B, polarities differently.
5.2.5 DB9 to Mini-DIN Adaptor (Cable 09)