Control Techniques UD70, User Manual

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UD70
Issue code: 70nu2
7-2 Reference
CLOCK task
The
CLOCK
task is used for time-critical monitoring of the Drive and
commands to the Drive (eg. controlled acceleration or deceleration ramp).
The
CLOCK
task is executed on a fixed timebase, asynchronously to the
Drive. The actual timebase used depends on the set-up parameter (see Set-
up Parameters in Chapter 10 Parameters), which can range from 5ms to
200ms).
Example This example produces a sine wave.
CLOCK{
#1.21 = SIN (rad)*1000
rad = rad+0.01
IF rad>6.283185 THEN
rad = 0
ENDIF
}
SPEED task
The
SPEED
task is synchronized with the speed-control loop in the Unidrive.
This causes the execution frequency of the task to be determined by the
PWM switching frequency.
Drive Switching
frequency
SPEED task
timebase
kHz ms
Unidrive 3, 6 or 12 1.38
Unidrive 4.5 or 9 1.84