Pakscan IIE System Manual
126 of 132
Publication S177E V2.0 Issue 03/05
Serial Port 4 (the PS410 RS485 port)
Port 4 has a 9-way D-type female connector. The connections are
shown in the table for both 2 and 4 wire connections. Internal
links on the PS410 card select between 2 and 4 wire.
The RS485 port has a true tri-state output allowing 2-wire
communications to be used. The master station uses a 2-wire
RS485 highway. If a 4-wire RS485 highway is needed it must be
taken from this port and a PS410 fitted in the rack.
The master station is a slave on the RS485 highway.
Ethernet Port
The Ethernet port uses a standard RJ45 socket for communication and is normally connected to a
switch by a straight cable. If the port is used to connect directly to a PC then a cross over cable must
be used.
Port 4 – RS485
Pin No.
2 wire
Function
4 wire
Function
1 NC NC
2 NC NC
3 Data
–
Tx –
4 RTS
–
Rx –
5
Signal
Ground
Signal
Ground
6 NC NC
7 NC NC
8 Data
+
Tx +
9 RTS
+
Rx +
Master Station
Tx+
Tx-
Rx+
Rx-
1
2
3
6
Hub/Switch
Straight through cable
Cable wiring
Pin 1
RJ45 Jack
Connector
1
2
3
6
Tx+
Tx-
Rx+
Rx-
RJ45 Jack
Connector
Fig 43: Connecting to a Hub or Switch
Master Station
Tx+
Tx-
Rx+
Rx-
1
2
3
6
PC Ethernet
Interface
Cross Over cable
Cable wiring
Pin 1
RJ45 Jack
Connector
3
6
1
2
Rx+
Rx-
Tx+
Tx-
RJ45 Jack
Connector
Fig 44: Connecting directly to a PC