10.3
Design of the RS 485 repeater (6ES7972-0AA01-0XA0)
Design
The table below shows the design and functions of the RS 485 repeater.
Description and functions of the RS 485 repeater
1
2
3
4
5
6
7
8
9
2
10
11
12
DC
24 V
L+ M PEM 5.2
SIEMENS
RS 485-REPEATER
ON
A1B1 A1 B1
A2 B2 A2 B2
PG
OP
DP2
ON
DP1
(1)
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").
(2)
Shielding clamp for the strain relief and grounding of the bus cable of bus segments 1 or 2
(3)
Terminals for the bus cable of bus segment 1
(4)
Terminating resistance for bus segment 1
(5)
LED for bus segment 1
(6)
OFF switch
(= isolate bus segments from each other, for example, for commissioning)
(7)
LED for bus segment 2
(8)
Terminating resistance for bus segment 2
(9)
Terminals for the bus cable of bus segment 2
(10)
Slide for mounting and removing the RS 485 repeater on the DIN rail
(11)
Interface for PG/OP on bus segment 1
(12)
LED 24 V supply voltage
RS 485 repeater
10.3 Design of the RS 485 repeater (6ES7972-0AA01-0XA0)
S7-400 Automation System Module Data
Reference Manual, Ausgabe 11/2016, A5E00850736-08
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