Principles Of Operation; Electronic Control; Loading; Lid Lock Control - Fisher & Paykel DEGX1 Service Manual

3.5

Principles of Operation

1.1.1

Electronic Control

The 120V or 220/240V power supply is connected to the
motor control module which rectifies to DC for use by its
own controller and peripherals, and also for the sensor
and display module. The motor control module has an
optically isolated serial communications port to the
sensor module from which it receives commands for
operating the drum motor and the heater(s). The motor
control module does the actual control of those devices.
The sensor module is responsible for the overall control
of the dryer, including the input and output of all other
peripherals. The sensor module controls the lid lock and
the drum door actuator, senses the drum position and
speed, measures. the exhaust duct temperature through
the exhaust sensor and measures the dampness of the
clothes load via the sensor bars.
The algorithm for when the heaters are turned on and
off, and also for the speed and direction of the motor, is
implemented within the sensor module, but the switching of the elements or gas heater, and control of
the motor, is done by the motor control module in response to the commands from the sensor module.
When the mains power is first applied to or restored to the sensor module, the dryer will endeavour to
continue operating from when the power was lost. If mains power was lost during a drying cycle, it will
continue to dry to the same set dryness level, otherwise the machine will return to have the drum door
open and the lid unlocked.
The display module is a "Dumb" module and user interface that passes user settings to the sensor
module and displays information in the form of LED displays transmitted from the sensor module.
3.5.2

Loading

The dryer always stops with the drum door open. The user places the drying load into the drum,
closes the lid, pushes the Power button, selects the required cycle and presses the Start/Pause
button. The lid will lock, the drum will rotate and the door grabber will slide the drum door closed. The
door grabber will then move clear of the drum.
3.5.3

Lid Lock Control

™
SmartLoad has a lock installed in the lid to provide added safety while the dryer is operating. It
ensures that the lid cannot be opened while the drum is rotating.
The lid lock is a mechanism driven by a DC solenoid and prevents the lid being opened when the drum
is rotating. If the lid lock mechanism is not engaged for any reason, including open circuit or short
circuit, a "Locked" is not assumed. If unable to lock after the user has requested a start, a User
Warning will be given.
The LID LOCKED LED (above the Start/Pause button) comes on when the lid is locked to tell the user
when they cannot open the lid.
§
When the LID LOCKED LED is illuminated, the lid is locked and the lid cannot be opened.
§
When the LID LOCKED LED is not illuminated, the lid is not locked and the lid can be opened.
§
If the LID LOCKED LED is flashing, the lidlock is in the process of locking or unlocking, (i.e. while
the dryer coasts down or Start/Pause has been pressed). During this stage the lid cannot be
opened.
Sensor Module
Motor Control Module
9
Display Module