Components Description - Simag SD 23 Bedienungsanleitung

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II PORTION HARVEST CYCLE
Electrical components (Loads) ....... ON
Compressor ........................................
Fan motor (SD 22÷60 ON) .................
Hot gas valve .....................................
Water inlet valve .................................
Water pump ........................................
Contactor coil .....................................
Timer motor ........................................
Electric Controls .............................. ON
Conctats 3-4 evaporator thermostat ..
Conctats 3-2 evaporator thermostat ..
Bin thermostat ....................................
Conctats COM-NO timer microswitch
Conctats COM-NC timer microswitch
Pressure control (SD22÷60W) (SD80÷210A)
OPERATING CHARACTERISTICS
On air cooled models during the freezing cycle
the discharge pressure is kept between 8÷10
bars (110÷140 psig) SD 22÷80, 15,5÷20 bars
(215÷280 psig) SD 125-210.
At the same time the suction pressure will
gradually decline, reaching its lowest point just
before harvest. Compressor amps experience a
similar drop.

COMPONENTS DESCRIPTION

A. MASTER SWITCH
Fitted on the front side of the unit cabinet the
master switch has to be used to start-up and to
stop the ice maker operation.
In connection with it there is the green monitor
light.
B. EVAPORATOR THERMOSTAT
The evaporator thermostat with its sensing bulb
intimately in contact with the refrigerant outlet
tube from the evaporator, senses the evaporating
refrigerant temperature (which declines in the
course of the freezing cycle) and when this one
reaches the pre-set value, it switches its contacts
from 3-4 to 3-2 to activate the finishing cycle (2nd
phase) which has a pre-set extension determined
by the large diameter lobe of the timer cam.
C. BIN THERMOSTAT
The bin thermostat, which has its sensing bulb
downward into the storage bin, shuts-OFF
automatically the icemaker when the ice storage
bin is filled and ice contacts its bulb. Being it
connected in series with the front microswitch of
the timer, it causes the unit shut-off only at the
end of the freezing cycle, when the ice cubes are
completed.
After ice is removed from the bin and its bulb
warm-up it allows the unit to restart from the
beginning of the harvest cycle which, in the
OFF
circumstance, is more likely a water filling cycle.
•
•
D. TIMER
•
•
Equipped with two microswitches which plungers
•
ride one timer cam, the timer is located inside the
•
control box.
The function of the timer begins when activated
•
by the cube size control (evap. thermostat).
The large diameter lobe of its cam determines
OFF
the 2nd freezing cycle portion length, while the
•
cam small diameter lobe, determines the time
•
cycle for the harvest sequence.
•
The timer cam can be adjusted to vary the defrost
• time as required.
•
• WARNING. Never set the defrost time for
longer than 4 minutes as this will
jeopardize the compressor motor
windings.
It goes without saying that an extension of the
defrost period will directly reduce the timed portion
of the freezing cycle and viceversa.
Consequently any variation made at the timer
cam setting requires a compensation adjustment,
very fine and very accurate, of the evaporator
thermostat.
E. CLEANING SWITCH
The cleaning switch is located on the edge of the
control box and it can be switched in two different
positions which are:
Operation Supply power directly to the
Cleaning
When positioned on "II CLEAN" with the shut-off
valve closed the water pump primes the cleaning
or the bactericide solution allover the unit water
system to generate a good cleaning and sanitizing
action of the ice maker.
NOTE. It is recommended to avoid the rinsing,
after the sanitation of the unit water system,
as any bactericide coating, which is beneficial
to limit the bacteria growth, left-over in the
system may be removed.
F. HI PRESSURE CONTROL
Used either on air (SD 80-125-210 A) and water
(SD 22÷60W) cooled ice makers it functions to
maintain the head pressure within the preset
values of 8÷10 bars (110÷140 psig) SD 22÷80,
and 15,5÷20 bars (215÷280 psig) SD 125-210,
by intermittently activating the fan motor (in the
air cooled models) and the water inlet valve to the
condenser (in the water cooled models SD 22-
23-30-40-60).
compressor motor or, on models
SD 80, SD 125 and SD 210, directly
to the contactor coil.
Shuts-off the compressor so that
only the water pump and the water
inlet valve will remain in operation.