Electrolux EIFLW55H MB, Technical & Service Manual

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1-8
Basic Information
Mass Damper Operation
The mass damper is a simple assembly consisting of
a heavy mass supported by gel. This device reduces
cabinet vibration through the dissipation of energy
coming from “gel” deformation. The use of the mass
damper is effective for a wide range of drum speeds and
installation conditions.
Drive Motor Operation
The motor is an induction, three phase AC motor that
varies speeds when the voltage from the speed control
board varies in frequency and amount. The motor has a
tachogenerator that inputs the speed of the motor to the
speed control board.
Speed Control
The speed control board is mounted to the base plate
of the washer in the left rear corner of the washer. The
speed control board controls the following operations:
1. The speed of the drive motor is controlled by
converting input line to neutral single phase 60
Hertz voltage, to a varying frequency, three phase
output voltage from zero to 300 VAC. By varying the
amount, frequency, and polarity of the voltage and
comparing the input from the tachogenerator on the
drive motor, the speed control board can operate the
drive motor at a preprogrammed speed and
direction.
2. The balance of the load in the washer is monitored
during the spin cycle by converting the sine wave
from the tachogenerator to square waves and
comparing the distance between the square waves.
If this distance exceeds a specified parameter, the
wash load is determined to be unbalanced and the
washer responds accordingly.
Concrete
Mass Damper
Mass Damper Mounted on Unit
Mass Damper Cross Section