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Siemens Desigo Room automation - Engineering, mounting and installation CM111043en_13
Smart Infrastrructure Ethernet network 2020-04-30
· The next device has no AC 24 V power when a room automation station is
removed. The connection exists only on the board, but not on the terminal block.
· The Ethernet switch is inactive when a room automation station has no AC 24 V
power. The next devices, if in line topology, are disconnected from the network.
For secure operation of the system it is recommended to supply each room
automation station separately with AC 24 V.
9.3 Cables
Room automation stations are connected to one another via switches and Ethernet
cables with RJ45 connectors.
The following conditions must be met:
· Standard Ethernet cable min. category 5
· Shielded or unshielded
STP (Shielded Twisted Pair) or UTP (Unshielded Twisted Pair).
· Length between switch and Room automation station max. 100 m / 328 ft.
· Length between Room automation stations Max. 100 m / 328 ft.
· Number of devices under a line topology max. 20.
· Standard IT product at 100 MB or 1 GB.
Additional information:
· Desigo Technical principles manual [1], Section 3 (overview), 16 (network view)
and 18 (system limits).
· Ethernet, TCP/IP as well as BACnet on Ethernet/IP principles [6].
· Practitioner's guide IP networks for building automation [10]
· IT Security in Desigo Installations [11]
9.4 Power over Ethernet (PoE)
"Effective signal and power supply on same cable".
Power over Ethernet (PoE) is a simple solution to supply power to room operator
units consuming only little power. This saves a power cable and associated
installation costs. PoE allows for installing Ethernet devices also in hard-to-access
locations or areas where too many cables are an issue.
For more information on Power over Ethernet (PoE), see also [10], CM110666,
Section 3.6.1, Power over Ethernet.
Note!
Availability /
reliability
Bus cable and length
Switch
Reference documents
Benefits