How The Electronic Cuber Works
Water System:
Freeze:
The water pump forces water to the top of the
evaporators. The un-frozen water falls thru the
cube deflectors and back into the reservoir. As
water is turned into ice, the water level in the
reservoir falls, and the machine will re-fill the
reservoir once during the freeze cycle.
At the point where the cubes are fully formed, the
water level sensor indicates to the System
Controller that it is time to begin the Harvest cycle.
Harvest:
At the beginning of Harvest, the water pump shuts
off and the purge valve opens. The purge valve
remains open for 74 seconds. No water will drain
until the water pump restarts. The water pump will
start at a variable time depending upon the
amount of water rinse that has been set.
After the purge valve has closed, the inlet water
valve opens and water flows into the ice machine.
The water valve will NOT be open the complete
length of the harvest cycle.
The inlet water valve will “top off” the reservoir at
the beginning of the next freeze cycle.
The System Controller operates the ice machine by
monitoring several input measures and switching
various loads on and off.
Controller Inputs:
1. Reservoir water temperature. This is measured
by a thermistor located in the water pump outlet.
2. Discharge line temperature. This is measured
by a thermistor located on the compressor
discharge line.
3. Water level. This is measured by an infrared
sensor and float. The float rises and falls with the
water level, and switches the sensor on and off as it
moves.
4. Bin fill level. The thermostat in the bin is used to
switch the machine on and off. The electric eyes in
the cube outlet port will also control the machine if
the bin thermostat sticks in an ON position.
5. Time to last cube. This is measured by a set of
electric eyes in the cube outlet port. During harvest
individual ice cubes pass between the
photo-electric eyes and the interruption of the
signal from the emitter to the receiver signals to the
controller that ice is being released.
5. Time. The controller measures and compares
how long it takes for various events to happen. It
stores that data for future reference.
Controller Outputs:
A. 24 volt:
•
1. Lights
•
2. Inlet water valve
•
3. Hot Gas Valve
•
4. Contactor Coil
•
5. Harvest Bypass Valve Coil
B. High Voltage
•
1. Water Pump
•
2. Purge Valve
CME2006R
July 1998
Page 23
