Siemens SIMATIC NET PROFIBUS Owner's Manual page 169

Table 5-1 Description and Functions of the RS-485 Repeater
Layout of the Repeater
DC
L+ M PE M 5.2
10 10 24 V 24 V
A1 B1 A1 B1 A1 B1 A1 B1
ON
È DP1
PG
OFF
OP
DP2
ON
SIEMENS SIEMENS
RS 485-REPEATER
A2 B2 A2 B2
1
) If the terminating resistor is activated, the right-hand bus attachment is disconnected (see
Figure 5-3) !
Note
Terminal M5.2 of the power supply (see Table 5-1, no. À) is used as the reference
ground for signal measurements if problems occur and must not be wired up.
PROFIBUS Networks SIMATIC NET
6GK1970-5CA20-0AA1 Release 2 05/2000
No.
À
Terminal for connecting the power supply of the RS 485
repeater (pin "M5.2" is the reference ground if you want to
measure the voltage between terminals "A2" and "B2").
À À
Á
Shield clamp for strain relief and grounding the LAN cable of
Á
bus segment 1 or bus segment 2
Â
Terminal for the LAN cable of bus segment 1
 Â
Ã
Terminating resistor for bus segment 1
Ä
Switch for OFF state
Ã
(= Disconnect bus segments 1 and 2, for example, during
11
Ä
commissioning)
12
Å
Å
Terminating resistor for bus segment 2
Æ
Terminal for the LAN cable of bus segment 2
Ç
Catch for mounting and removing the RS-485 repeater on a
Æ
standard rail
È
Interface for PG/OP on bus segment 1
Á Á
LED 24 V power supply
10
Ç
LED indicating bus activity on segment 1
11
LED indicating bus activity on segment 2
12
Active Components for RS-485 Networks
Function
1
)
1
)
5-3