Siemens SIPROTEC 7UT613 series Manual page 375

Table 3-21 Assignment of the connectors for the various serial interfaces
RS232
Pin No.
1
2 RxD
3 TxD
4 –
5 GND
6 –
7 RTS
8 CTS
9 –
1)
Pin 7 also carries the RTS signal with RS232 level when operated as RS485 interface. Pin 7 must therefore not be con-
nected!
Termination
Time Synchronisa-
tion Interface
7UT613/63x Manual
C53000-G1176-C160-2
With data cables, the connections are designated according to DIN 66020 and ISO
2110:
• TxD = Data output
• RxD = Data input
• RTS = Request to send
• CTS = Clear to send
• GND = Signal/Chassis Ground
The cable shield is to be grounded at both ends. For extremely EMC-prone environ-
ments, the GND may be connected via a separate individually shielded wire pair to
improve immunity to interference.
The following table lists the assignments of the DSUB port for the various serial inter-
faces.
RS485 Profibus FMS Slave, RS485
Profibus DP Slave, RS485
Shield (with shield ends electrically connected)
–
A/A' (RxD/TxD-N)
–
C/C' (GND)
– +5 V (max. load < 100 mA)
1)
–
B/B' (RxD/TxD-P)
–
The RS485 interfaces are capable of half-duplex service with the signals A/A' and B/B'
with a common reference potential C/C' (GND). It must be checked that the terminat-
ing resistors are connected only for the respectively last device of the bus but not for
all other devices of the bus.
The jumpers for the terminating resistors are located on the interface module RS485
(see figure 3-13) or PROFIBUS RS485 (see figure 3-14).
It is also possible that the terminating resistors are arranged externally (figure 3-15).
If the bus is extended, verify again that only the last device on the bus has the termi-
nating resistors connected, and that the other devices on the bus do not.
Either 5 VDC, 12 VDC or 24 VDC time synchronisation signals can be processed if the
connections are made as indicated in the table below.
–
B/B' (RxD/TxD-P)
CNTR-A (TTL)
C/C' (GND)
–
A/A' (RxD/TxD-N)
–
3.2 Checking Connections
Modbus RS485 Ethernet
DNP3.0 RS485
EN 100
–
R
RTS (TTL level)
EARTH1
VCC1
–
B
–
existent
Tx+
Tx–
Rx+
—
—
Rx–
—
—
non
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