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PRINCIPLE OF OPERATION
When the opposite situation occures, i.e. the
condenser temperature gets below the pre-fixed
ACCUMULATOR
CAPILLARY TUBE
COMPRESSOR
FAN MOTOR
limit, the temperature sensor changes again its
electrical resistance reducing therefore the
current flow to the P.C. Board to cause a tempo-
rary stop of the Fan Motor.
NOTE. In case the condenser temperature
probe senses that the condenser temperatu-
°
re has rised to 70
C (160
following abnormal reasons:
CLOGGED CONDENSER
FAN MOTOR OUT OF OPERATION
AMBIENT TEMPERATURE HIGHER THEN
°
°
43
C (110
F)
it causes the total and immediate SHUT-
OFF of the machine in order to prevent the
unit from operating in abnormal and
dangerous conditions. When the ice maker
stops on account of this protective device,
there is a simultaneous glowing of the 2nd
RED LED, warning the user of the Hi Tem-
perature situation. After having eliminated
the source of the excessive condenser tem-
perature, to restart the ice machine it is
necessary to push the RE-SET button or
De-engerize and Re-engerize the unit.
The 2nd RED LED starts blinking and
three minutes later the flaker unit resume its
normal operating mode.
The refrigerant suction or Low-pressure sets in
normal ambient conditions (21 °C/70
value of 1 bar (14 psig) after few minutes from
the unit start-up.
This value can vary of 0.1 or 0.2 bar (1.5
in relation to the water temperture variations
influencing the freezer cylinder.
NOTE. If, after ten minutes from the unit start
up, no ice is made and the evaporating
temperature detected by the evaporator
sensor is higher than -1 ° C (30 ° F) the ice
maker stops and the 3RD WARNING
YELLOW LED blinks.
EVAPORATOR
DISCHARGE LINE
°
F) for one of the
°F
) - on the
÷
3 psig)
Page 11
MECHANICAL SYSTEM
The mechanical systemr consists basically of a
gear motor assembly which drives, through a
ratched coupling, a worn shaft or auger
placed on its vertical axis within the freezing
cylinder.
The gear motor is made of a single phase electric
motor with a permanent capacitor. This motor is
directly fitted in the gear case through which it
drives - in counter clockwise rotation at a speed
of 9.5 r.p.m. - the freezer auger being linked to it
by the ratched coupling.
NOTE. In the event the gear motor will tend
to rotate in the wrong direction or not
rotating at all the unit will stop
immediately with the glowing of the 3RD
WARNING YELLOW LED on account of
the intervention of the Electromagnetic
Safety Device - based on Hall Effect principle.
After having diagnosed and eliminated the
source of the failure, to restart the unit it is
necessary to press the RE-SET push button
or switch OFF and ON the power line main
disconnnect switch (Fig. 7).
The RED LED will start blinking and after
3 minutes the ice maker will resume its total
operations by running first the gear motor
and then the compressor.
FIG. 7
When the gear motor rotating speed is slowed
below 1300 r.p.m. from the normal speed of
1400 r.p.m. the Electromagnetic Safety Device
transmits an electrical signal to the
MICROPROCESSOR to stop immediately the
unit operations like it occures for the wrong
rotation, with the lighting-up of the 3RD YELLOW
WARNING LED. This to relieve from the
excessive load all the electrical and mechanical
components of the entire Drive System and extend
their durability.
NOTE. After having diagnosed and eliminated
the source of the gear motor slow rotation to
restart the unit it is necessary to press the
RE-SET push button or switch OFF and ON
the power line main switch.
NOTE. Any time the machine stops in alarm
the front four LED's start to blink.
GEMD270A
STEADY
WRONG-NO-SLOW ROTATION GEAR MOTOR
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