Siemens Simatic S7-300 - Example: Maximum Distances in the MPI Subnet

Configuring
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
4-41
Example: Maximum distances in the MPI subnet
The figure below shows you:
• a possible MPI Subnet configuration
• maximum distances possible in an MPI subnet
• the principle of "Line extension" using RS485 repeaters
max. 50 m
max. 50 m
Terminating resistance on
S7-300
spur line
PG connected via spur line for maintenance purposes
0
0 ... x
MPI addresses of nodes
7
34
9
OP 27
PG
PG
OP 27
RS 485-
Repeater
RS 485-
Repeater
max.
1000 m
11
OP 27
S7-300
6
SF
BUSF
DC5V
FRCE
RUN
STOP
SIEMENS
S7-300
10
SF
BUSF
DC5V
FRCE
RUN
STOP
SIEMENS
S7-300
5
SF
BUSF
DC5V
FRCE
RUN
STOP
SIEMENS
SF
BUSF
DC5V
FRCE
RUN
STOP
SIEMENS
S7-300
8
SF
BUSF
DC5V
FRCE
RUN
STOP
SIEMENS
Figure 4-15 Example: Maximum distances in the MPI subnet