Basic Documentation
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Siemens RWD Primary Controls Modbus Interface CB1P3099en_01
Building Technologies Commissioning SEZ50MB 27.10.2009
For best performance, the single BUS topology is highly recommended.
A
MODBUS RS485 Type
Max Cable Length = 1000 m
…
+
-
Ref GND
Ref
- +
SEZ50MB
RS232
RWDxx
RS232
Ref
- +
SEZ50MB
RS232
RWDxx
RS232
Ref
- +
SEZ50MB
RS232
RWDxx
RS232
+
-
Termination
Resistance of
both ends
150
Ω
RX
TX
GND
TX
RX
GND
D+
D-
RS232
-
TO
-
RS485
Converter
Isolated Converter Recommended
B
USB
USB
…
+
-
Ref
Ref
- +
SEZ50MB
RS232
RWDxx
RS232
Ref
- +
SEZ50MB
RS232
RWDxx
RS232
Ref
- +
SEZ50MB
RS232
RWDxx
RS232
+
-
Termination
Resistance
of both ends
150
Ω
GND
D+
D
-
MODBUS RS485 Type
Max Cable Length = 1000 m
RS232
-
TO
-
RS485
Converter
Isolated Converter Recommended
Inconsistent and wrong wirings to G & G0 supply terminals for internetworking
SEZ50MB Modbus system may cause permanent damages to the devices.
RWDxx
G G0
G G0
AC 24 V SELV
Modbus
RS232
RS232
SEZ50MB
G G0
RWDxx
G G0
SEZ50MB
G G0
G G0
AC 24 V SELV
RWDxx
G G0
SEZ50MB
G G0
G G0
AC 24 V SELV
SEZ50MB
G G0
RWDxx
G G0
Modbus
RS232
RS232
G G0
AC 24 V SELV
Note:
For each SEZ50MB device connected with RWDxx operated at AC 230V, it
gets its AC 24 V from AC 230 V by a SELV electrically isolated transformer (e.g.
Siemens SEM62.1 or SEM62.2). To ensure best performance, this isolated transformer
should not power other devices.
SEZ50MB
G G0
RWDxx
G G0
SEZ50MB
G G0
G G0
AC 24 V SELV
RWDxx
L N
L N
AC 230 V
Modbus
RS232
RS232
RS232
SEZ50MB
G G0
G G0
AC 24 V SELV
RWDxx
G G0
Modbus Connection
Power Supplies