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Service Manual
Ne
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E
lectronic Cold Platform 2005
Edition
2005.03.25
Language
E
nglish
Compressor Operation:
The compressor serves to compress the gas in the
thermodynamic circuit in order to generate the nec-
essary cooling capacity to chill the appliance com-
partments.
The compressor is managed by the Main PCB with
the aid of a relay and a triac that trips, in parallel with
the relay, only at the time of compressor power-on
and power-off to protect the relay from electrical arc-
ing when the contact is opened and closed, other-
wise the compressor is powered exclusively via the
relay when it is running.
The compressor is started whenever a cooling de-
mand is received.
I
n certain conditions the compressor will remain stopped despite the presence cooling demands; these
situations are as follows:
Compressor protection:
The compressor switches on once a minimum safety time interval (parameterised in the EEPROM) has
elapsed since the last power off, thereby allowing the pressure of gas to reach a point of equilibrium in the
refrigerant circuit. The same minimum safety time is observed in the event of a mains power interruption
(voluntary or involuntary). This compressor protection strategy is observed only after the product has been
operating continuously for a number of hours defined in the memory. This facilitates the execution of factory
tests.
Long periods of activity:
I
f the compressor runs for a time greater than a value defined in the EEPROM memory, it is switched off
even in the presence of a cooling demand from either or both compartments. This feature is designed to
protect the compressor.
Fridge Fan Operation: (only in Digit models)
The fan is designed to distribute cold air uniformly inside the fridge compartment. The fan is controlled by
I
f the temperature measured by the freezer air sensor is above the On threshold a cooling demand is
activated thereby starting the compressor; on the contrary, if the freezer air sensor detects a temperature
lower than the Off temperature, the cooling demand is deactivated.
Refrigerator Compartment Adjustment:
Refrigerator temperature control is managed by the
PCB according to the temperature measured by the
refrigerator air sensor in relation to the user settings
on the interface.
I
f the temperature measured by the refrigerator air
sensor is above the On threshold, a cooling demand
is activated thereby starting the compressor and the refrigerator fan (if present); on the contrary, if the
refrigerator air sensor detects a temperature lower than the Off temperature, the cooling demand is deac-
tivated.
LOADS MANAG
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Summary of Contents for New electronic cold platform 2005
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