Carrier Transicold 69NT40-561-001 Operation And Service Manual page 63

Code Title
Configurable Functions - Cd27 through Cd37 are user-selectable functions. The operator can change the value
of these functions to meet the operational needs of the container.
Cd27 Defrost Interval
(Hours or Automatic)
Cd28 Temperature Units
(Degrees C or
Degrees F)
Cd29 Failure Action (Mode)
Cd30 In-Range Tolerance
Table 4–5 Controller Function Codes
Description
This is the desired period of time between defrost cycles. Factory default is "AU-
TO". Refer to Section 4.3.23
CnF11 determines whether the operator will be allowed to chose "OFF" as a de-
frost interval option.
CnF64 determines whether the operator will be allowed to choose "PuLS" as a
defrost interval option. For units operating with "PuLS" selected, defrost interval
is determined by the unit temperature setpoint and the Evaporator Fan Pulsing
Temperature Setting (Cd60). When the unit temperature setpoint is equal to or
less than the Evaporator Fan Pulsing Temperature Setting, the defrost interval
is set to 6 hours. Otherwise, the defrost interval is determined using the Automat-
ic Defrost Interval Determination logic. In either case, "PuLS" remains displayed
in this function select code.
After a new Defrost Interval is selected, the previously selected Interval is used
until the next defrost termination, the next time the DTT contacts are OPEN, or
the next time power to the control is interrupted. If the previous value or the new
value is "OFF", the newly selected value will be used immediately.
If any Auto Pretrip sequence is initiated, Cd27 will be set to 'AUTO' unless
CnF49 (OEM Reset) is set to "Custom" AND CnF64 (Evaporator Fan Pulsing
Logic) configuration variable is set to IN, in which case Cd27 will be set to
"PuLS".
This code determines the temperature units (C or F) that will be used for all tem-
perature displays. The user selects C or F by selecting function code Cd28 and
pressing the ENTER key. The factory default value is Celsius units. This function
code will display "-----" if CnF34 is set to F.
If all of the control sensors are out of range (alarm code AL26) or there is a probe
circuit calibration failure (alarm code AL27), the unit will enter the shutdown state
defined by this setting. The user selects one of four possible actions as follows:
A - Full Cooling (Compressor is on, economized operation.)
b - Partial Cooling (Compressor is on, standard operation.)
C - Evaporator Fan Only (Evaporator fans on high speed, not applicable with fro-
zen set points.)
d - Full System Shutdown - Factory Default (Shut down every component in the
unit.)
The in-range tolerance will determine the temperature band around the set point
which will be designated as in-range.
For normal temperature control, control temperature is considered in range if it
is within setpoint in-range Tolerance. There are four possible values:
1 = +/- 0.5°C (+/-0.9°F)
2 = +/- 1.0°C (+/-1.8°F)
3 = +/- 1.5°C (+/-2.7°F)
4 = +/- 2.0°C (+/-3.6°F) - Factory Default
If the control temperature is in-range, the green IN-RANGE light will be illuminated.
In-range tolerance shall be set to +/- 2.0?C upon activation of dehumidification
or bulb mode (Cd33, Cd35, Cd48).
When CCPC is actively controlling, in-range tolerance is not considered.
"-----" will be displayed whenever Dehumidification or Bulb mode is enabled or
when CCPC with six hour re-activation is actively controlling.
"-----" will be displayed whenever Frozen Economy Mode is operating.
4–27
for information on Defrost Interval.
T-340