VFD68 Variable Frequency Drives
52
PWM Frequency, Audible Motor Noise, and EMI
Using the default setting (P. 72 = 1, frequency = 1 kHz), electromagnetic interference (EMI) radiation and
leakage current from the wiring between the VFD68 drive and the motor is low; however, there is a high level of
audible motor noise. As the setting for P. 72 increases (up to P. 72 = 15, frequency = 15 kHz), audible motor
noise decreases, while EMI radiation and leakage current increases.
If the audible noise from the VFD is too great with P.72 set to 1, increase the setting to 4 and listen to the
audible noise. To minimize the EMI radiation, use the smallest number possible for P. 72.
Adjusting the Default Parameters
VFD68Bxx and VFD68Cxx Drives
Enter the Parameter Adjustment Mode
1.
Remove the jumper that connects terminal SD to terminal STF.
!
CAUTION: Risk of Property Damage.
Do not apply power to the system before checking all wiring connections. Short circuited or
improperly connected wires may result in permanent damage to the equipment.
MISE EN GARDE: Risque de dégâts matériels.
Ne pas mettre le système sous tension avant d'avoir vérifié tous les raccords de câblage. Des fils
formant un court-circuit ou connectés de façon incorrecte risquent d'endommager irrémédiablement
l'équipement.
IMPORTANT:
Remove the jumper to stop the motor before you change the parameter values.
Figure 38: Applications Using 4–20 mA Transducers
