As the manual on-off circuit breaker switch is pushed to "on", an electrical circuit is completed to the
gearmotor via the circuit breaker gearmotor overload, power relay/contactor, gearmotor delay thermostat
and the bin thermostat. After the previous circuit has been completed the condenser fan motor will start
as will the compressor (via the high pressure control, the compressor starting relay and low ambient
On-Off Switch/Circuit Breaker
This switch interrupts power to the entire unit. The switch has a circuit breaker incorporated into its'
design. This circuit breaker will trip out in the event the gearmotor draws to high of amps. In such an
event the power is interrupted to the unit. To reset the circuit breaker and reestablish power to the unit,
push the switch to the "off" position and then back to the "on" position.
This is electrically in "series" with the ice making system. When the bin is full, the contact opens,
terminating power to the machine.
High Pressure Control
Switch contact will open at 450 PSI for R404a breaking the circuit to the compressor. This control is
Gearmotor Start Relay
This is a current type relay which means as the gearmotor run winding comes "on" the line, the current
draw initially is relatively heavy through the relay coil (coil is in series with run winding). It then acts like a
normal relay and the N.O. start contact "makes", completing a circuit through the start capacitor to the
start winding. As the gearmotor picks up speed, the amp draw through the relay coil drops off allowing
the armature to return to its normal position (start contact "opens"). This action removes the start winding
from the circuit.
This relay controls the compressor power only.
Fan Cycling Switch
The function of this switch is to maintain condensing pressures at a satisfactory level during-low ambient
conditions. The switch breaks the circuit to the condenser fan motor at 205 PSI and makes the circuit at
This thermostat keeps the gearmotor running until the suction line temperature reaches 45 after the full
bin switch terminates power to the power relay.
Compressor Start Relay
This is a current type relay and contains a N.O. contact which is connected in series with the start
winding of the compressor. The relay coil is electrically in series with the run winding. When power is
applied, the compressor draws high current which sets up a magnetic field in the magnet coil which
causes the relay to operate, closing the relay contact. As the compressor approaches operating speed,
the current flowing through the coil decreases, permitting the relay contact to open, thereby opening the
© 2004, IMI Cornelius Inc.
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Self-Contained Flaked Ice Maker Service Manual
Publication Number: 166240010SER