7 data transfer, Data transfer – Lenze E84DGFCP User Manual
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Communication manual 8400 motec PROFIBUS
Data transfer
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EDS84DMOTPBUS EN 3.0 - 11/2011
7
Data transfer
The PROFIBUS master and the controller communicate through the exchange of data
telegrams via PROFIBUS. The user data area of the data telegram contains parameter data
or process data. In the controller, different communication channels are assigned to the
parameter data and process data.
Communication channels
The process data channel transmits process data.
– The process data serve to control the drive controller.
– The host (master) can directly access the process data. In the PLC, for instance, the
data are directly assigned to the I/O area.
– Process data are not saved in the controller.
– Process data are transferred cyclically between the host (master) and the controllers
(slaves) (permanent exchange of current input / output data).
– Process data are, for instance, setpoints, actual values, control words and status
words.
– The Inverter Drive 8400 motec can exchange a maximum of 8 process data words
(16 bits/word) per direction.
– In addition to the process data, digital and analog input information can also be
queried. These signals are set permanently to 2 additional data words which must be
parameterised correspondingly in the HW manager.
Digital and analog input information
The parameter data channel serves to transfer parameter data.
– The parameter data channel provides access to all Lenze codes.
– In general, the parameter data transfer is not time-critical.
– Parameter data are, for instance, operating parameters, motor data and diagnostic
information.
– Parameter changes must be stored via code C00002 of the Inverter Drive 8400
motec.
Note!
Observe the direction of the information flow!
• Process input data (Rx data):
– Process data from the controller (slave) to the master
• Process output data (Tx data):
– Process data from the master to the controller (slave)