Appendix – Lenze ECSCPxxx User Manual
Page 413
Appendix
Communication with MotionBus/system bus (CAN)
Structure of the CAN data telegram
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413
EDBCSXP064 EN 8.0
User data
The user data area of the CAN telegram either contains network management data,
process data or parameter data:
User data
Description
Network management data
(NMT data)
The information serves to establish communication via the CAN network
Process data
(PDO, Process Data Objects)
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Process data are transmitted via the process data channel.
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The process data serve to control the controller.
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Process data can be accessed directly by the higher−level host system.
The data are, for instance, stored directly in the I/O area of the PLC. It is
necessary that the data can be exchanged between the host system
and the controller within the shortest time possible. In this connection,
small amounts of data can be transferred cyclically.
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Process data are transmitted between the higher−level host system and
the controllers to ensure a permanent exchange of current input and
output data.
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Process data are not stored in the controller.
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Process data are, for instance, setpoints and actual values.
Parameter data
(SDO, Service Data Objects)
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Parameter data are transferred via the parameter data channel and
acknowledged by the receiver, i.e. the receiver gets a feedback whether
the transmission was successful.
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Parameter data of Lenze devices are called codes.
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The parameter data channel enables access to all Lenze codes and all
CANopen indexes.
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Parameters are set, for instance, for the initial commissioning of a
plant or when material of a production machine is exchanged.
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Usually the transfer of parameters is not time−critical.
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Parameter changes are stored in the controller.
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Parameter data are, for instance, operating parameters, diagnostic
information and motor data.
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Tip!
The other signals refer to the transfer features of the CAN telegram that are
not described in these instructions.
For further information visit the homepage of the CAN user organisation CiA
(CAN in Automation): www.can−cia.org.