Siemens Simatic S7-300 - Appearance of the RS 485 Repeater; (6 ES7972-0 AA01-0 XA0)

RS 485 Repeater
7-3
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
7.2 Appearance of the RS 485 Repeater;
(6ES7972-0AA01-0XA0)
The table below shows the appearance of the RS 485 repeater and lists its
functions.
Table 7-3 Description and Functions of the RS 485 Repeater
Repeater Design
No. Function
24 VDC
L+ M PE M 5.2

10
 Connection for the RS 485 repeater power supply (pin “M5.2” is
the ground reference, if you want to measure the voltage
difference between terminals “A2” and “B2”).


10
 Shield clamp for the strain relief and grounding of the bus cable
of bus segment 1 or bus segment 2

 Terminals for the bus cable of bus segment 1

A1 B1 A1 B1
 Terminating resistance for bus segment 1



A1 B1 A1 B1
PG
OP
11
12
OFF
ON
DP1
 Switch for OFF operating mode
(= isolate bus segments from each other – for example, for
startup

OP
DP2
12
OFF
 Terminating resistance for bus segment 2
SIEMENS
ON
 Terminals for the bus cable of bus segment 2
SIEMENS
RS 485-REPEATER

A2 B2 A2 B2
 Slide for mounting and removing the RS 485 repeater on the
standard rail

 Interface for programming device/OP in bus segment 1

10
LED 24 V supply voltage

11
LED for bus segment 1
12
LED for bus segment 2