Saia-Burgess
Controls Ltd.
Hardware Manual for the PCD3 Series│Document 26/789; Version E 5│31.01.2005
Communication interfaces
4
4-11
Serial interfaces on I/O module Slot 0
Block diagram:
Not all manufacturers use the same connection configuration, so the data lines may
need to be crossed
The potential difference between PGND and the data lines Rx-Tx, /Rx-/Tx (and
SGND) is limited to 50V by a suppressor capacitor.
For installation details, see manual 26/740 “Installation components for RS 485 net-
works”
75176
Driver
RS485
OPTO-0601
Transmit
Receive
EN
TXD
RXD
RTS
SGND
+5VE
330 Ohm
150 Ohm
330 Ohm
D
/D
DC
DC
+5V
PGND
SGND
+5VE
SGND