Nidec Control Techniques HVAC Drive H300 HMI Bypass, Installation And Commissioning Manual

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HMI Bypass Controller Installation and Commissioning Guide 25
3.2.2 Autotune
The VFD is able to perform either a stationary or a rotating autotune. The
motor must be at a standstill before an autotune is enabled. A rotating
autotune should be used whenever possible, so the measured value of power
factor of the motor is used by the drive.
Autotune : is an algorithm that the VFD uses to detect physical characteristics
of the motor in order to improve control and efficiency.
To perform an autotune, first select either STATIONARY or ROTATING
(recommended) and then hit the AUTOTUNE button. The motor must be at a
standstill before an autotune is enabled.
Note: The drive will not perform an autotune if there is an existing fault or if
the STO input is not closed.
Note: A rotating autotune should only be used if the motor is uncoupled. To
clear incorrect values calculated from a coupled rotating autotune perform a
stationary autotune. Performing a stationary autotune will clear the incorrect
values and reset motor rated power factor to factory default (0.85).
WARNING
A rotating autotune will cause the motor to accelerate up to 40 Hz in the
direction selected regardless of the reference provided. Once complete the
motor will coast to a stop.