Connection Of The Profibus/Dp Cable - Mitsubishi Electric MELSEC ST Series Installation Manual

Connection of the PROFIBUS/DP Cable

4.5
The shielded two-wire PROFIBUS/DP line is connected to the 9-pin D-SUB socket of the head
station. The socket has the following pin assignment:
Pin Layout of the socket
To connect to the PROFIBUS use a 9-pin D-SUB plug like the PROFICON-PLUS plugs and
PROFICON PLUS PG plugs from the MELSEC line of accessories. The two wires of the
PROFIBUS line and the shielding are connected to pins 1, 3, and 8.
If the head module is the last station in a branch, then the PROFIBUS/DP line must be termi-
nated with resistors. For the PROFICON-PLUS and PROFICON-PLUS PG plugs the
resistances are already installed and can be switched on. For a plug without integrated resis-
tors, three resistors must be connected according to the following circuit diagram. The resistors
are not included in the module's scope of delivery.
MELSEC ST Series
PIN
5
9
6
1
Head station ST1H-PB
RxD/TxD-P
RxD/TxD-N
VP (6)
RxD/TxD-P (3)
RxD/TxD-N (8)
DGND (5)
Symbol
Name
1 — SHIELD
2 — M24V
3 B/Bn RxD/TxD-P
4 — CNTR-P
5 C/Cn DGND
6 — VP
7 — P24V
8 A/An RxD/TxD-N
9 — CNTR-N
1
Shield
PROFIBUS/DP cable
3
8
= 390 Ω ±2%, min. 1/4 W
R
U
= 220 Ω ±2%, min. 1/4 W
R
tA
= 390 Ω ±2%, min. 1/4 W
R
d
Installation
Meaning
Shield, protective earth
Not used
Sent and received data (P)
Not used
Data Ground, Datenmasse
Voltage +
Not used
Sent and received data (N)
Not used
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