ABB ACS880 Series, Руководство по прошивке

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4. Set the gain, integration time, derivation time, and the PID output levels ( 40.32 ,
40.33 , 40.34 , 40.36 and 40.37 ).
5. The PID controller output is shown by parameter 40.1 . Select it as the source
of, for example, 22.11 .
Sleep function for process PID control
The sleep function can be used in PID control applications that involve relatively
long periods of low demand (for example, a tank is at level), During such periods,
the sleep function saves energy by stopping the motor completely, instead of
running the motor slowly below the efficient operating range of the system. When
the feedback changes, the PID controller wakes the drive up.
Note: The sleep function is disabled when mechanical brake control (see page 113 )
is active.
Example: The drive controls a pressure boost pump. The water consumption falls
at night. As a consequence, the process PID controller decreases the motor speed.
However, due to natural losses in the pipes and the low efficiency of the centrifugal
pump at low speeds, the motor would never stop rotating. The sleep function
detects the slow rotation and stops unnecessary pumping after the sleep delay
has passed. The drive shifts into sleep mode, still monitoring the pressure. The
pumping resumes when the pressure falls under the wake-up level (setpoint -
wake-up deviation) and the wake-up delay has passed.
110 Program features