UMG 96-PA / UMG 96-PA-MID / UMG 96-PA-MID+
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8.5 Bus structure
In a bus structure:
·Connect all devices in line.
·Each device has its own address.
·One segment contains up to 32 nodes/devices.
At the beginning and end of a segment, the
cable must be terminated with resistors (bus
termination, 120 ohms, 1/4 W)!
·With more than 32 participants, use repeaters
(line amplifiers) to connect 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.
Slave
Fig.
Representation of a bus structure
Slave
Slave
Slave
Repeater
Slave
Slave
Slave
Master
Power supply necessary
Bus terminator on
T
T
T
T
T
Master - e.g. UMG 604-PRO
Slave - UMG 96PA
