Bosch WAT28400 Repair Instructions page 21

Design and function
Measurement 3 starts after successful operation of measurements 1 and 2. The
unbalance detected determines the rotary speed of the spin cycle approved for the
range 1000 rpm ≤ U ≤ 1550 rpm.
In case of high unbalance during measurement 3, the spin cycle is cancelled.
If the 3D/3G sensor is faulty, the appliance spins at a maximum of
1000 rpm.
Appliances with no 3D/3G sensor solely determine the unbalance with
measurement 1. If measurement 1 determines an impermissible unbalance, the
control unit limits the rotary speed of the drum in order to improve the distribution of
the laundry. Then, measurement 1 is restarted.
A maximum of 15 start-ups to the rotary speed are possible for the measurement.
Fig. 16: Process schematic for unbalance measurement without 3D/3G sensor
A Measurement 1
B Reduction of the rotary speed
The unbalance determined specifies the rotary speed during the spin cycle and the
duration of the acceleration to the rotary speed. If there is a high unbalance, the
appliance will spin with reduced rotary speed and shorter acceleration.
2017-05-22 / DIS 113_58300000186503_ara_en_c
C Decreased rotary speed after start-up attempt
Copyright by BSH Hausgeräte GmbH
The electronics offset the decreased rotary speed with the longer
duration of the spin cycle.
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