B.ICE BIN LEVEL SENSOR
The ice bin level temperature sensor, secured to one of the storage bin walls, stops the operation of the entire ice maker at the end of the defrost cycle when its sensing probe (in contact with the stored ice) reaches the temperature of +2˚C (35˚F) lighting up, in the meantime, the third RED
LED.
Once the ice is removed from the sensing probe, its temperature progressively rises up and as it reaches the value of +4.5˚C (40˚F) the ice bin level temperature sensor transmits a low voltage current flow to the P.C. BOARD to restart the operation of the unit.
NOTE: The ice maker, after the interruption of its operation due to the ice level control
By changing the combination of the DIP SWITCH Keys numbers 8 and 9 it is possible to change the range of the ice level control temperature sensor. This is shown in table D, keeping its cut out temperature always at +2˚C (35˚F).
C.P.C. BOARD (Data processor)
The P.C. BOARD, fitted in its plastic box located in the front of the unit, consists of two separated printed circuits one at high and the other at low voltage integrated with a program selector; of six aligned LEDS monitoring to the service engineer the operation of the machine; of one DIP SWITCH with ten keys; of input terminals for the leads of the two sensor probes and of input and output terminals for the leads of the ice maker electrical wires.
The P.C. BOARD is the brain of the system and it processes, through its microprocessor, the signals received from the two sensors in order to control the operation of the different electrical components of the ice maker (compressor, water pump, solenoid valves, etc.).
By turning the program selector it is possible to put the unit in the following different situations:
CLEANING/RINSING The water pump is the only electrical component in operation and it must be used during the cleaning or the rinsing procedure of the water system of ice machine.
STAND BY The unit remains under electrical power but OUT of operation. It can be used by the service engineer in order to stop the unit during the service and inspection operations.
IN OPERATION The unit is running through the freezing and defrost cycles stopping automatically only at full bin situation.
The six LEDS (not visible through the panel) placed in a vertical row in the front of the P.C. BOARD, monitor, from the top to the bottom, the following situations:
GREEN LIGHT Unit under electrical power
RED LIGHTUnit
RED LIGHTEvaporator sensor at
RED LIGHTUnit in freezing cycle mode
The microprocessor of the P.C. BOARD has also the important function to establish the length of the defrost cycle Ts in relation with the duration of the second phase of the freezing cycle or time T2 as shown in Table B. Page 12.
6.5Dip Switch
The P.C. BOARD which controls the entire operation of the ice maker, has a DIP SWITCH with ten switching keys which allow set up of the microprocessor program in order to extend or to shorten the length of freezing cycle in relation to the different models and versions of ice machines and to modify the sensing range of the ice bin level temperature sensor.
The 1st DIP SWITCH key is used to supply power to the water pump during the first
The 2nd DIP SWITCH key allows a rapid check up
DURING THE AUTOMATIC OPERATION OF THE ICE MAKER THIS KEY MUST BE SET IN OFF POSITION.
ATTENTION The check up of the P.C. BOARD output must be performed in a very short time in order to avoid frequent start and stop (every few seconds) of the electrical components which may damage them - especially the compressor.
The setting of the DIP SWITCH keys 3, 4, 5, 6 and 7 determines the length of the 3rd phase of freezing cycle (controlled by the electronic timer) as detailed in Table B. Page 12.
The DIP SWITCH keys 8 and 9 setting determines the range between cut in and cut out temperature of the ice bin level temperature sensor as specified in Table D. Page 12.
The 10th DIP SWITCH key is used to change the setting of the evaporator temperature sensor from
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