Specifications

 Serial Interfaces (COM1,COM2,COM3,COM4)

This interface is used to connect an RS-232C cable. A D-sub 9-pin plug connector is used.

Interfaces

• The PL unit’s serial port is not isolated. When the host (PLC) unit is

also not isolated, be sure to connect the #5 SG (Signal Ground) terminal

to reduce the risk of damaging the RS-232C circuit.

• Inside the PL unit, the SG (Signal Ground) and FG (Frame Ground)

terminals are connected.

• When connecting an external device to the PL using the SG terminal, be

sure to check that no short-circuit loop is created when you setup the

system.

Stacking Metal Fittings #4-40 inch (UNC)

Pin Arrangement Pin No.

Signal

Name

Direction Meaning

1 CD Input Carrier Detect

2 RD(RXD) Input Receive Data

3 SD(TXD) Output Send Data

4 ER(DTR) Output Data Terminal Ready

5 SG - Signal Ground

6 DR(DSR) Input Data Set Ready

7 RS(RTS) Output Request to Send

8 CS(CTS) Input Send Possible

CI(RI)/

VCC

In/ Output

Called status display /

+5V+

5% Output

*1 Number 9 pin’s [RI/+5V]changeover is good only for COM2 and COM3. The factory

default setting is [RI]. For COM1 and COM4, [RI] can be available.

Shell FG -

Frame Ground

(Common with SG)

• Whenever changing RI/5V changeover switch, be sure to first turn the

PL’s power supply OFF, then remove the Rear Maintenance Cover. The

switch is on the board.

SEE

For how to remove the Rear Maintenance Cover, refer to “PL-6930/PL-

7930 Series User Manual”.