Scotsman CME506R AutoIQ - Manual (Page 19)

How The Electronic Cuber Works
This section is intended for the technician. It is not
necessary for the normal operation and
maintenance of the machine.
The AutoIQ Controller operates the ice machine by
monitoring several input measures and switching
various loads on and off.
Water System:
Water flows into the ice machine during the
harvest cycle from thru the inlet water valve. The
water valve will NOT be open the complete length
of the harvest cycle. The water pump operates
whenever the machine is on, and it forces water to
the top of the evaporators. The un-frozen water
falls thru the cube deflector and back into the
reservoir. As water is turned into ice, the water
level in the reservoir falls, and at the point where
the cubes are fully formed, the water level sensor
indicates to the AutoIQ Controller that it is time to
begin the Harvest cycle.
During the Harvest cycle, water again enters the
water reservoir, and overfills it to rinse the
reservoir of accumulated minerals. It does NOT
overflow for a fixed amount of time, but for a time
determined by the AutoIQ Controller.
The water pump will be off for a short period of
time at the beginning of Harvest.
Refrigeration System:
The refrigeration system is similar to that of most
commercial cube ice machines. Heat is removed
from the water and discharged out the condenser
during the freeze cycle. As liquid refrigerant
passes thru the Thermostatic Expansion Valve, it
enters the bottom of the evaporators, and will form
on the bottom first. When cubes need to be
released (Harvest) the Hot Gas Bypass Valve is
opened and Hot discharge gas flows directly from
the compressor to the evaporator inlets. This
warms up the evaporators and the surface of the
ice frozen to the evaporator surface melts. Ice then
falls into the bin.
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. This is measured by a set of
electric eyes in the cube outlet port. If ice fills the
bin, it will block the “eyes".
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. LEDs
• 2. Inlet water valve
• 3. Hot Gas Valve
• 4. Contactor Coil
• 5. Liquid Line Valve Coil
B. High Voltage
• 1. Water Pump
CME506R, 656R, 806R: AutoIQ Cubers
January 2000
Page 19