Lenze 8400 motec Series - User Data Types; Communication Phases and Network Management

Data transfer
Communication phases/network management
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Lenze · Decentralised frequency inverter 8400 motec (CANopen option) · EDS84DMOTCAN EN 4.0 - 02/2019
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7.1.2 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.
• You can control the inverter by means of the process data.
• Process data are not
saved in the inverter.
• Process data are transmitted between the host (master) and the inverters (slaves), providing for
a continous exchange of current input and output data.
• Process data usually are unscaled/scalable raw data.
• Process data are, for instance, setpoints and actual values.
•The exact meaning of the PDO file contents is determined via the function block editor (FB
Editor) in the I/O level or via the PDO mapping.
Parameter data
(SDOs – service data objects)
• Parameter data are the CANopen indexes or, in the case of Lenze devices, the codes.
• The parameters are, for instance, set for the initial system set-up during commissioning or when
material is changed on the production machine.
• Parameter data are transmitted as SDOs via the parameter data channel. They are
acknowledged by the receiver, i.e. the sender receives 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 saved automatically in the inverter until mains switching.
• Generally the parameter transfer is not time-critical.
• Parameter data are, for instance, operating parameters, motor data and diagnostic information.
7.2 Communication phases/network management
With regard to communication via the system bus, the inverter knows the following states: