UMG 509-PRO
42
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8.4
Bus structure
·All devices are connected in a bus structure
(line).
·Each device has its own address within the bus
(see also Programming parameters).
·Up to 32 nodes can be connected together in
one segment.
·At the beginning and end of a segment, the
cable is to be terminated with resistors (bus
termination, 120 ohms, 1/4 W).
·If there are more than 32 nodes, repeaters (line
amplifiers) must be used to connect the individu-
al segments.
·Devices with bus termination switched on must
be powered.
·It is recommended that the master be placed at
the end of a segment.
·If the master is replaced with the bus termination
switched on, the bus is out of operation.
·The bus can become unstable if a slave with bus
termination switched on is replaced or is de-en-
ergized.
·Devices that are not involved in the bus termina-
tion can be replaced without the bus becoming
unstable.
Fig. Bus structure
Slave
Slave
Slave
Slave
Slave
Slave
Repeater
Slave
Slave
Slave
Slave
Master
Power supply necessary
Bus termination on
T
T
T
T
T
INFORMATION
CAT cables are not suitable for the bus wiring.
Use the recommended cable types for this
purpose.
