User Manual

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Siemens TX-I/O Engineering and installation guide CM110562en_13
Building Technologies Principles of electrical design 2019-05-15
The island bus expansion module has DIP switches to set the functions "bus master"
and "bus terminator".
Communication can be interrupted when the switches are incorrectly set; there are no
obvious symptoms, however, when a switch is incorrectly set.
24. When both BM switches are on, the island bus expansion modules serves as the
island bus master.
This is required for decentralized sub-islands. The automation station or the BIM
is the master for local sub-island.
25. When both BT switches are on, the island bus expansion module serves as the
bus termination.
Required on the segment end and on the local sub-island .
10562z146
Bus-Master
(AS, BIM)
BM = ON
BT = OFF
BM = ON
BT = ON
BM = ON
BT = ON
BM = ON
BT = OFF
BM = OFF
BT = ON
BM = OFF
BT = ON
BM = ON
BT = OFF
BM = ON
BT = ON
BM = ON
BT = OFF
Key = I/O row with automation station or BIM
= I/O row
= Cable island bus
= Cable island bus expansion
BM, BT = DIP switches on island bus expansion module
26. As is the case for all island bus devices, the island bus expansion module can be
installed during operation.
Bus master, bus
connection rules
Hot plugging