Specifications

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22 TORQUE (TORQUE CURVE SELECTION)
This parameter is used to select whether the output of the drive follows a constant or variable
V/Hz curve. The following selections are available:
CONSTANT Use for constant torque applications to optimize torque.
VARIABLE Use for variable torque applications to optimize energy savings.
CT / NOCMP Use for constant torque applications that require full overload
capacity at low speeds (see Parameter 17 - MOTOR OL).
23 CARRIER (CARRIER FREQUENCY)
This parameter sets the carrier frequency, or switching frequency of the output IGBT’s.
Higher switching rates result in less audible noise to be emitted from the motor, but the
efficiency of the drive decreases as the carrier frequency increases. Therefore, this parameter
should be set to the lowest value which yields acceptable sound levels. Available settings
are: 2.5 kHz, 6 kHz, 8 kHz, 10 kHz, 12 kHz and 14 kHz.
NOTE 1: The 2.5 kHz carrier frequency setting is a variable carrier. The carrier frequency
remains fixed at 1.5 kHz up to 25 Hz output frequency. Above 25 Hz, the carrier is a fixed
multiple of 60 times the drive’s output frequency. For example, if the output frequency of
the drive was set to 45 Hz, the carrier frequency would be 2.7 kHz (45 Hz x 60 = 2700 Hz).
The other settings are constant carriers that remain fixed for the entire speed range.
NOTE 2: The ability to operate a drive at higher carrier frequencies is dependent on the
drive horsepower rating, driven load, drive enclosure, and the ambient temperature.
Operation above 8kHz requires derating the drive by multiplying the output current rating by
the following factors: 0.94 at 10 kHz, 0.89 at 12 kHz, and 0.83 at 14 kHz.
25 START (START MODE)
Warning
Automatic start of equipment may result in damage to equipment and/or injury to
personnel! Automatic start should only be used on equipment that is inaccessible to
personnel.
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