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It is advisable to use a screened cable for connections to external
devices. Remember to connect the screen to the metal part of the shell
of the 9-pin connector on one end.
RS422 connections
If the COM2 serial port is configured with the RS422 standard, you
must:
• Make a bridge connection between pin 6 and pin 8 to connect the
termination resistance.
CAUTION
Limits to use envisaged for standard RS422:
Maximum transmission distance: 1200 m / 4000ft
Maximum voltage at ends: +/- 7V
It is advisable to use a screened cable of the "twisted pair" type for
connections to external devices. Remember to connect the screen to
the metal part of the shell of the 9-pin connector on one end.
RS485 connections
If the COM2 serial port is configured with the RS485 standard, you
must:
•
Connect pins 9 and 6 (DATA +) and pins 1 and 7 (DATA -) together
•
Make a bridge connection between pin 6 and pin 8 so as to connect
the termination resistance. This operation must be carried out on
the rst and last device connected together.
CAUTION
Limits to
use envisaged for standard RS485:
Maximum transmission
distance = 1200 m
Maximum voltage at ends = ± 7V
It is
advisable to use a screened cable of the "twisted pair" type for
connections to external devices. Remember to connect the
screen to the metal part of the shell of the 9-pin connector.
Maximum number of terminals that can be connected = 16