Control Techniques Nidec SI-EtherCAT User Manual page 116

Figure 8-1 Profile Cycle Timing
Drive Sync
Waveform
(OptSync)
Profile Cycles
Control Loop
Cycles (current
torque)
Critical Task
(task length
varies with
amount of data
exchanged)
Pre-Critical Task
(task length
varies with
amount of data
exchanged)
Post-Critical
Task (task length
varies with
amount of data
exchanged).
After Drive
Critical update
period has
completed.
116
250µs OptSync Interrupt
time
62.5µs*
*
This time can vary according to drive
frequency (which can change during
operation to reduce temperature in drive)
75µs*
70µs*
75µs*
70µs*
75µs*
70µs*
SI-EtherCAT User Guide