Siemens SIPROTEC 7SS523 V3.2 Manual page 352

Appendix
D-SUB Connectors
Connections for
FOs
336
Pin PC port
No.
1
−
2 RxD
3 TxD
4
−
5 GND
6
−
7
−
8
−
9
−
1 Pin 7 carries the RTS signal with RS232 level even if operated as RS 485 interface.
Therefore pin 7 must not be connected!
2 Pin 4 is assigned but cannot be used
The transmit and receive connections of the FO cables are identified by the symbols
for transmit (output) and
Service port (F)
RS 232
Shield electrically connected with collar
−
RxD
TxD A/A' (RxD/TxD−N)
−
GND C/C' (GND)
−
RTS
CTS B/B' (RxD/TxD−P)
−
for receive (input).
Time synchronizing
port (E)
RS 485
P24_TSIG
−
P5_TSIG
−
M_TSIG
−
−
1
P12_TSIG
−
−
C53000-G1176-C182-1
2
−
−
−
−
−
7SS52 V4 Manual