Lenze 9400 - Manual (Page 301)

Lenze · Servo-Inverter 9400 HighLine · Reference manual · DMS 10.0 EN · 11/2013 · TD05/06
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9 "CAN on board" system bus
9.4 Structure of the CAN data telegram
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9.4.2 User data
All nodes communicate by exchanging data telegrams via the system bus. The user data area of the
CAN telegram either contains network management data or parameter data or process data:
Network management data
(NMT data)
• Control information on start, stop, reset, etc. of communication to specific nodes or to all nodes
of the CAN network.
Process data
(PDOs – process data objects)
• Process data are transferred via the process data channel.
• Process data can be used to control the controller.
• Process data are not saved to the controller.
• Process data are transmitted between host system and nodes to ensure continuous exchange
of current input and output data.
• Process data usually are unscaled/scalable raw data.
• Process data are, for instance, setpoints and actual values.
Parameter data
(SDOs – service data objects)
• Parameter data are the CANopen indexes or, in case of Lenze devices, the codes.
• Parameters are, for instance, used for one-off plant setting during commissioning or when the
material is changed on a production machine.
• Parameter data are transmitted as SDOs via the parameter data channel. They are
acknowledged by the receiver, i.e. the transmitter gets a feedback about the transmission being
successful or not.
• The parameter data channel enables access to all Lenze codes and CANopen indexes.
• Parameter changes are automatically saved to the controller until mains switching.
• In general, the parameter transfer is not time-critical.
• Parameter data are, for instance, operating parameters, diagnostic information and motor data.