Acoustic Noise Or Vibration - Danfoss VLT HVAC Basic Drive FC 101 Design Manual

General Specifications and ...

8.3 Acoustic Noise or Vibration

If the motor or the equipment driven by the motor, e.g., a fan blade, is making noise or vibrations at certain frequencies, try
the following:
•
Speed Bypass, parameter group 4-6* Speed Bypass
•
Overmodulation, 14-03 Overmodulation set to [0] Off
•
Switching pattern and switching frequency parameter group 14-0* Inverter Switching
•
Resonance Dampening, 1-64 Resonance Dampening
The acoustic noise from the adjustable frequency drive comes from three sources:
1. DC intermediate circuit coils
2. Integral fan
3. RFI filter choke
Frame
H1
H2
H3
H4
H5
H6
H7
H8
H9
H10
I2
I3
I4
I6
I7
I8
Table 8.9 Typical Values Measured at a Distance of 3.3 ft [1 m] from the Unit
MG18C522
Design Guide
Level [dBA]
57.3
59.5
53.8
64
63.7
71.5
67.5 (75 kW 71.5 dB)
73.5
60
62.9
50.2
54
60.8
70
62
65.6
Danfoss A/S © Rev. 2014-01-14 All rights reserved.
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