Rockwell Automation 1336VT AC DRIVE 5-300AMP (2-160KW) PROGRAMMING MANUAL - Manual (Page 47)

Local and Serial Port Parameters
Firmware Version 1.01-3.01
Chapter 3
3-33
Parameter 44 Ċ Dwell Time
Freq P R
P R Enter Seconds
0
10
0
Read and Write
Units
Minimum Value
Maximum Value
Factory Setting
This function sets the time in seconds the drive will hold at the dwell
frequency, Parameter 43.
Parameter 45 Ċ PWM Frequency
Freq P R
P R Enter kHz
.40
2.00
.40
Read and Write
Units
Minimum Value
Maximum Value
Factory Setting
This parameter adjusts the minimum carrier frequency used to generate the
PWM output waveform. In the range from 0 to 95 Hz, the carrier frequency
will be 21 times the generated output frequency, but no less than this value.
As an example, the factory setting of 0.4 is a 400 Hz carrier. This carrier
will be used from 0 to approximately 19 Hz of drive output. Above 19 Hz,
the carrier will change proportionally to the drive output frequency.
Increasing the PWM frequency usually reduces audible motor noise at low
speeds, but may result in instability on lightly loaded motors. Reducing the
PWM frequency improves motor stability, but may result in increased
audible noise.
If the PWM frequency is changed while the drive is running, the drive will
perform the PWM frequency change only when the output frequency is
changed and not before.