Lenze EtherCAT Controller-based Automation - Manual (Page 37)

Lenze · Controller-based Automation · EtherCAT® Communication Manual · DMS 6.4 EN · 04/2014 · TD17
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6 Synchronisation with "Distributed clocks" (DC)
6.1 Synchronous communication
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6.1 Synchronous communication
The DC synchronisation provides for a phase-synchronous operation of master and slaves:
Within one bus cycle the setpoints are accepted and the actual values are detected in the fieldbus
at exactly the same time.
If the Lenze Controller (master) is in synch with the distributed clocks, the data (actual values)
acquired by the slave are sent to the master at the end of the bus cycle and data from the master
(setpoint values) are sent to the slaves for processing. .
When the next DC synchronisation event occurs, the data are accepted.
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Note!
• The DC synchronisation is only carried out in the "Operational" state.
• After an "Out-of-sync" occurrence, the EtherCAT master synchronises the slaves.
Successful synchronisation is indicated by means of the "In-Sync" message (see
Diagnostic tabs of the EtherCAT master ( 164) ).