Technical data

Active components
4.1 Active components for RS485 networks
PROFIBUS Network Manual
System Manual, Edition 04/2009, C79000-G8976-C124-03
69
Design of the RS-485 repeater
Table 4- 1 Description and functions of the RS-485 repeater
Description and functions of the RS
485 repeater
No. Function
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 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 resistor for bus segment 1
)1
5 Switch for OFF state
(= Disconnect bus segments 1 and 2, for example, during commissioning)
6 Terminating resistor for bus segment 2
)1
7 Terminals for the bus cable of bus segment 2
8 Slide for mounting and removing the RS-485 repeater on a DIN rail
9 Interface for PG/OP on bus segment 1
10 LED 24V power supply
11 LED indicating bus activity on segment 1
DC
24 V
L+ M PE M 5.2
SIEMENS
RS 485-REPEATER
ON
A1 B1 A1 B1
A2 B2 A2 B2
PG
OP
DP2
OFF
ON
DP1













12 LED indicating bus activity on segment 2
)
1
If the terminating resistor is activated, the right-hand bus terminals are disconnected
Note
Pin M5.2 of the power supply is used as the ground reference for signal measurements if
problems occur and must not be connected up.
Technical specifications
Table 4- 2 Technical specifications of the RS-485 repeater
Power supply
Rated voltage
Ripple (static limit)
24 V DC
20.4 V DC to 28.8 V DC
Current consumption at rated voltage
Without load on PG/OP socket
Load on PG/OP socket (5 V/90 mA)
Load on PG/OP socket (24 V/100 mA)
200 mA
230 mA
300 mA
Connectors
• Bus cables
• Power supply
2 terminal blocks
Terminal block