Siemens Simatic CFU, Commissioning Manual

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Operation planning
4
4.1 Rules for the operation
Topology
● PROFINET IO
You can integrate the CFU into the following structures on the PROFINET IO:
Line, star and ring topology (MRP), as well as PROFINET system redundancy (S2): Max.
number of nodes: 256
● Freely configurable channels (DIQ)
The following configuration is possible at the digital inputs / outputs:
Line topology (per channel "DIQ; DIQ<n>": 1 sensor or 1 actuator)
● CFU PA only: PROFIBUS PA
The following configuration is possible on the PROFIBUS PA connections:
Line topology (for each fieldbus connection "FIELDBUS; FB<n>": 1 field device)
Distances
The permissible distance between the bus nodes depends on the following factors:
● PROFINET
– Cable type (electrical/optical)
– Transmission path (use of amplifiers / repeaters)
● CFU PA only: PROFIBUS PA
– Transmission path: Max. of 120 m to the field device (amplifiers or repeaters are
impermissible in the transmission path)
Dependency on the ambient temperature
● Load current (total current of the encoder supplies "DI" and the outputs "DQ")
The total permissible load current of all freely configurable channels of a CFU depends on
the ambient temperature and mounting position.
You can find information on this in section "Mechanical and climatic ambient conditions for
operation (Page 160)".
● Cable temperature
You can find information on this in section "Mechanical and climatic ambient conditions for
operation (Page 160)".
● BusAdapter
Ensure that the BusAdapter is suitable for use at the respective ambient temperature.
You can find information about this in the documentation SIMATIC; Distributed I/O;
BusAdapter for distributed I/O.
SIMATIC CFU
Commissioning Manual, 08/2019, A5E39252870-AD
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