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7216549.01 - en
INSTALLATION AND OPERATING MANUAL
Application
Maximum distance
Total length of bus
cable
Section of bus cable
Number of M-Bus
devices
Maximum transmission
fr
equency
Small residential buildings
350 m
1000 m
0.8 mm
2
250
9600 Baud
Large residential buildings
350 m
4000 m
0.8 mm
250
2400 Baud
64
9600 Baud
Small districts
1000 m
4000 m
0.8 mm
2
64
2400 Baud
Medium districts
3000 m
5000 m
1.5 mm
2
64
2400 Baud
Larger districts
5000 m
7000 m
1.5 mm
2
16
300 Baud
Point-to-point
10.000 m
10.000 m
1.5 mm
2
1
300 Baud
Minimum bus voltage
•
The signal converter powers the bus network and therefore each connected M-Bus device generates a voltage drop
in the network.
•
For each M-Bus connected to the final points of the bus segments, the minimum bus voltage should be checked and
guaranteed.
•
The voltage drop at the ends of the bus segments id caused by the type of cable used, the distances, the route and
the number of connected devices (slave).
Cable diameter 8 mm
l
Length of cable [m]
n
Number of M-Bus devices
n
Maximum length of cable with equidistant distribution of devices
n
Maximum distance of cable with devices connected at the end of the bus cable
s
Equal to
n
but with a reduced signal due to the short circuit of an M-Bus device
Diagram of the length of the bus cable
0806_2403
