Control & Peripheral Functions; Power/Control Module - Fisher & Paykel RB90S64MKIW Service Manual

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Control & Peripheral Functions
The control system consists of the power/control module located alongside the water evaporation tray in the
front edge of the drawer cabinet.
compartment and connects to various sensors and actuators controlled by the power/control module. The
function and brief description of each of these units is defined in Section 8.1.1.
8.1.3

Power/Control Module

This module is the electronic brain and control centre of the refrigerator. It contains a microprocessor,
support circuitry and switching devices. The power/control module controls the compartment temperature by
sensing the temperature and drawer state and operating the compressor and fans accordingly. This module
also houses the alarm beeper.
The micro controller in the power/control module uses its internal memory for control; its ROM (Read Only
Memory) for program and fixed constant storage including tables, and the RAM (Random Access Memory)
for variable storage and access.
The power/control module contains a special type of memory device call an EEPROM. The information on
the fridge operation, faults and diagnostic information is stored in this memory.
temperature setting, the history of the temperatures (for approximately 18 hours), defrost history (the last 12
defrosts) and fault history. This will help the service person find and remedy the cause of a failure. All this
memory will be retained even when the fridge is disconnected from the mains power supply.
The beeper is used to signal prolonged drawer opening and other fault conditions:
• If the drawer is left open longer than 60seconds, the alarm will sound. This will repeat every 30 seconds
until the drawer is closed.
• If the drawer is left open longer than 5 minutes, the alarm will sound continuously and the interior lights
will turn off. The alarm will stop with the closing of the drawer or by pressing any button.
• All electronic faults, when detected, will cause the LEDs on the user interface to flash indicating the fault
code. The audible alarm will sound when the drawer is opened. The alarm will beep a number of times
representing the fault code number (refer to Section 10.1.2).
The cabinet module is located on the back wall of the produce
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They include the