Technical Overview; Chassis; Drawer Fronts; Electronics - Fisher & Paykel DishDrawer DD603 Service Manual

March 2004
3.0

TECHNICAL OVERVIEW

3.1

Chassis

The DishDrawer chassis is one complete assembly composed of 5 steel metal components locked together by a
proprietry riveting process. The chassis exterior is made of a lacquered electrogalvanised material called
Galvoclean.
Unlike most other dishwashers, the chassis assembly is a load carrying structure designed to impart stiffness to the
product and to ensure deflection is minimised.
The feet of the Double cabinet are assembled into the chassis by means of four steel inserts which are clinched in
place to form a permanent threaded connection.
The tub extends 520mm (20
the tub.
3.2

Drawer Fronts

Prefinished drawer fronts are formed from a painted, brushed or Iridium finish stainless steel blank. The drawer
fronts are attached to the tub by means of formed hooks and two pins which are inserted through either side of the
tub.
On the integrated model, the front panel supplied on each drawer is the mounting panel for the joinery finished
drawer front. The joinery finished drawer front is supplied by the customer.
3.3

Electronics

In the DD603/ DS603 (Phase 3) electronic controller the functions of controlling the motor as well as controlling the
user interface console have been combined into a single 16-bit Micro Controller on the main printed circuit board.
This Micro controller also controls a transformerless 85w switchmode power supply. This power supply utilises a
large dropping resistor on the heater plate in conjunction with phase control of the mains voltage in order to produce
a variable voltage rail. From this the controller can supply voltages from 5V to 85V to the various components in the
DishDrawer.
NOTE:- With power supplies of this nature all components regardless of supply voltage should be treated as live to
earth. i.e = supply voltage.
The user interface comprises a printed circuit board for front controls and a touch switch panel for internal controls.
The electronics can connect to a computer service tool via an optical light pen for fault finding and product
information.
The element is switched by one single pole relay. Overheat protection is effected by a short length of solder in series
with the dropper resistor track on the heater plate. In an overheat situation this solder melts causing the power
supply to go open circuit.
3.3.1

Tub Home Sensor

A tub home sensor is used to determine when the tub is closed and it is safe to start a cycle. The tub home sensor
consists of an inferred LED (sender) and an inferred transistor (receiver) mounted on the circuit board in the
controller. Inferred light is transmitted from the LED through an optical light pipe to the right hand side of the tub. The
inferred receiving transistor also has an optical light pipe leading from it out to the side of the tub. When the tub is
closed the two light pipes are optically connected via a prism mounted in the trim on the side of the chassis.
/ ") out of the cabinet by travelling along two rigidly attached slides on either side of
15
32
- 11 -
Manual 599082