Hardware Interface - Siemens SICAM P 7KG7755 Manual

4.2

Hardware Interface

Bus connection
Protocol
Max. line length
Insulation level
Bus termination
Power Meter, IEC 60870-5-103, Manual
E50417-B1076-C375-A4, Release 11.2012
9-pole D-SUB outlet
Pin Signal
1 Shield
2 -
3 A
4 RTS
5 GND
EXT
6 +5 V
EXT
7 -
8 B
9 -
Table 4-1 Pin assignment of the bus connector (D-SUB outlet)
semi-duplex
1000 m / 3300 ft.
AC 500 V
Bus termination via bus plug with integrated terminating resistors.
A
B
Figure 4-1 Recommended external termination circuit with open-line fail-safe
Shield / Operational ground
-
RS485 connection pin A
Directions control
Data transmission level (ground towards +5 V
Supply voltage for terminating resistors (DC +5 V, max. 100 mA)
-
RS485 connection pin B
-
+5 V
EXT
390 Ohm
220 Ohm
390 Ohm
GND
EXT
Technical Data
Meaning
)
EXT
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