Siemens SINAMICS S120 Series Function Manual page 34

Communication according to PROFIdrive
Controller, Supervisor and drive unit
Table 3- 2
Properties
As bus node
Send messages
Receive messages
Communication types
4 communication types are defined in the PROFIdrive profile:
● Cyclic data exchange via a cyclic data channel
Motion control systems require cyclically updated data in operation for open-loop and
closed-loop control tasks. This data must be sent to the drive units in the form of
setpoints or transmitted from the drive units in the form of actual values, via the
communications system. Transmission of this data is usually time-critical.
● Acyclic data exchange via an acyclic data channel
The PROFIdrive profile also provides an acyclic parameter channel to exchange
parameters between the controller – or the supervisor and drive units. Access to this data
is not time-critical.
● Alarm channel
Alarms are output on an event-driven basis, and show the occurrence and expiry of error
states.
● Isochronous mode
– Cyclic data exchange in a fixed time grid
– The controller and device are synchronized
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Properties of the Controller, Supervisor and drive units
Controller
Active
Permitted without external
request
Possible without any re-
strictions
Supervisor Drive unit
Passive
Only possible on request by the
Controller
Only receive and acknowledge
permitted
Function Manual, 12/2018, 6SL3097-5BD00-0BP0
Communication