Carrier NDK33BN0KB, Operation & Service Manual

Page: 92 / 270

62-61753-21 4-10
above the pre-programmed ProductShield Winter tem-
perature.
All of the ProductShield settings are in the Data List
(Refer to Table 3-1). The Data List will reflect the
ProductShield settings for the IntelliSet commodity that
is currently active.
NOTE
ProductShield does not operate within Sleep
Mode.
4.6.4 ProductShield Temperature Ranges
Each ProductShield setting allows the user to select a
ambient temperature range in which to operate.
The Minimum and Maximum range values can be set
to OFF, or any value from -19°F to +119°F (-28.3°C to
+48.3°C).
The examples below all use the same settings and
illustrate the differences in unit operation for the vari-
ous ProductShield selections.
a. ProductShield: Econo: Go To Start/Stop
Examples
The following examples apply in situations where all
other Start/Stop conditions have been met.
If the Minimum is set to 30°F (-1.1°C) and the Maxi-
mum is set to 42°F (5.6°C) and the
ambient air tem-
perature falls between these temperatures, the unit
operation can change to Econo Start/Stop.
If the Minimum is set to OFF and the Maximum is set
to 35°F (1.7°C) and the
ambient air temperature falls
below 35°F (1.7°C), the unit operation can change to
Econo Start/Stop.
If the Minimum is set to 70°F (21.1°) and the Maximum
is set to OFF and the
ambient air temperature is
above 70°F (1.7°C), the unit operation can change to
Econo Start/Stop.
b. ProductShield: Econo: Go To Continuous
Operation Examples
If the Minimum is set to 30°F (-1.1°C) and the Maxi-
mum is set to 42°F (5.6°C) and the
ambient air tem-
perature falls outside these temperatures, the unit
operation will change to Econo Continuous Operation.
If the Minimum is set to OFF and the Maximum is set
to 35°F (1.7°C) and the
ambient air temperature is
above 35°F (1.7°C), the unit operation will change to
Econo Continuous Operation.
If the Minimum is set to 70°F (21.1°) and the Maximum
is set to OFF and the
ambient air temperature is
below 70°F (1.7°C), the unit operation will change to
Econo Continuous Operation.
c. ProductShield: High Air Examples
If the Minimum is set to 15°F (-9.4°C) and the Maxi-
mum is set to 85°F (29.4°C) and the
ambient air tem-
perature falls outside these temperatures, the unit
operation will change to Econo High Air.
If the Minimum is set to OFF and the Maximum is set
to 35°CF (1.7°C) and the
ambient air temperature falls
above 35°F (1.7°C), the unit operation will change to
Econo High Air.
If the Minimum is set to 70°F (21.1°) and the Maximum
is set to OFF and the
ambient air temperature is
below 70°F (1.7°C), the unit operation will change to
Econo High Air.
4.7 PREPROGRAMMED SOFTWARE OVER-
RIDES
4.7.1 High Discharge Temperature
The microprocessor monitors the signal provided by
the compressor discharge temperature sensor. If com-
pressor temperature rises to the limit (refer to section
2.10), the system will enter Liquid Injection Mode. In
this mode the normally closed liquid injection valve
(LIV) will be pulsed or opened as required to allow flow
of refrigerant into the economizer connection, to cool
the compressor.
4.7.2 RAT & SAT Alarms Both Active
When both the RAT and SAT alarms are activated,
temperature control will enter Default Mode.

If Default Mode is entered when the setpoint is in
the Perishable Range (above -12°C [+10.4°F]), the
unit will shut down.

If Default Mode is entered when the setpoint is in
the Frozen Range (-12°C [+10.4°F] or below), the
unit will transition to Economized Mode. If in Engine
Operation, the engine will operate in low speed.
4.7.3 Engine Speed Overrides
With the complex control systems in use with the
LogiCOLD Microprocessor, there are many different
reasons the engine may be operating in either high
speed or in low speed besides the number of degrees
the refrigerated compartment temperature is away
from setpoint. This section lists the different factors
that determine the speed of the engine, in the order of
their priority.
Speed Control Solenoid Overrides in priority order are:
1. RAT & SAT Alarms Both Active
When both the RAT and SAT alarms are activated,
microprocessor control will enter Default Mode. Refer
to Section 4.7.2
2. High Speed To Low Speed Delay
When the unit is operating in high speed, and the mi-
croprocessor calls for low speed, the engine will re-
main in high speed until the high voltage current draw
is less than the Diesel Offset Maximum Amps Configu-
ration value, or for 40 seconds if the amperage is al-
ready lower than the Maximum Amps value. It will then
to go low speed.
3. Silent Mode
When the Silent Mode Functional Parameter is set to
ON, the unit will operate in low speed only