The Door Lock Unlocks The Door - Electrolux W4400H Service Manual

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The door lock unlocks the door
The programme unit requests door unlocking
4
by applying 0 V on input X92 of the door lock
controller.
The following check is made prior to unlocking
of the door:
• No water in drum - input X9 from level gu-
ard B2 is closed = 0 V
• Motor not engaged - input X94 from motor
controller U1 open = 5 V
• Drum not rotating - pulse frequency on input
X95 from rotation sensor B less than 0.4 Hz.
When the above conditions are met, the door
lock controller outputs an negative pulse on
output 96 to the door lock actuator, which then
unlocks the door. Micro switches S4a and S4b
now interrupt the actuator and the I/O card 1
relays lose all voltage to prevent the motor from
starting (no interlock signal on motor controller
input X02). The drain and water valves of the
machine are now disabled and the heater and
motor cannot be switched on.
Door and door lock
4
Door lock
control A1
X92
X9 X94 X96
X95
Level
Motor
X04
guard B2
control U1
M1
Rotation sensor B
Programme unit
A1
I/O card 1
X4
A11
X10 X5
X02
Door lock
A41
5225