Wascomat EXSM 230 S, Operating & Maintenance Manual

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37
Mechanical and electrical design
Motor control unit
The motor control unit communicates with the PCU board via a serial
duplex interface. With the aid of the MCU, the PCU can not only control the
speed the motor is to have at any given moment, but also control the
acceleration and deceleration rates the motor will use to reach the speed
commanded. The MCU constantly relays information back to the PCU
board on current operating status, e.g. whether everything is proceeding
without problems or if a fault or error has arisen.
The MCU can also supply data on the torque of the motor at constant speed
and when accelerating and decelerating. This data is used both for
calculating the weight of the wash load and for detecting any imbalance
present.
Take great care when using measuring instruments on the MCU,
since all components have a potential difference of approx. 300 V in
relation to earth and neutral.
The MCU will not be de-energised until 10-30 seconds after the
machine is isolated from the power supply and the motor has
stopped.
The green LED on the MCU board will remain lit for as long as there
are hazardous voltages present in components.
4711 A
Fig.
37
Fig.
39
37
230 V AC
Door lock switch
Input
lock sequence
X302
Relay output
X304
Motor
Serial communication
X301
Main input
X311
PCU
X312
X312
Motor
control unit