3--17
T-334
Table 3--5 Controller Function Codes (Sheet 2 of 4)
Cd25
Compressor Run
Time Remaining
Until Defrost
This code displays the time remaining until the unit goes into defrost (in tenths of
an hour). This value is based on the actual accumulated compressor running
time.
Cd26 Defrost Temperature
Sensor Reading
Defrost temperature sensor reading is displayed.
Configurable Functions
NOTE
Function codes 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)
There are two modes for defrost initiation, either user-selected timed intervals or
automatic control. The user-selected values are (OFF), 3, 6, 9, 12, 24 hours or
AUTO. The factory default is AUTO. Automatic defrost starts with an initial defrost
at 3 hours, then the interval to the next defrost is adjusted based on the accu-
mulation of ice on the evaporator coil. Following a start-up or after termination of
a defrost, the time will not begin counting down until the defrost temperature sen-
sor (DTS) reading falls below set point. If the reading of DTS rises above set
point any time during the timer count down, the interval is reset and the count-
down begins over. If DTS fails, alarm code AL60 is activated and control switches
over to the the return temperature sensor. The controller will act in the same man-
ner as with the DTS except the return temperature sensor reading will be used.
Defrost Interval Timer Value (Configuration variable CnF23):
If the software is
configured to “SAv” (save) for this option, the value of the defrost interval timer
will be saved at power down and restored at power up. This option prevents short
power interruptions from resetting an almost expired defrost interval, and possibly
delaying a needed defrost cycle.
NOTE
The defrost interval timer counts only during compressor run time.
Cd28 Temperature Units
(C or F)
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
pushing the ENTER key. The factory default value is Celsius units.
NOTE
This function code will display “
-----“ if
Configuration Variable CnF34 is set to
F.
Cd29 Failure Action
(Mode)
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. SMV subject to pressure
and current limit.)
B - Partial Cooling (Compressor is on, standard operation. SMV subject to pressure
and current limit.)
C - Evaporator Fan Only (Evaporator fans on high speed, not applicable with frozen
set points.)
D - Full System Shutdown - Factory Default (Shut down every component in the unit.)
Cd30 In-Range Tolerance
The in-range tolerance will determine the band of temperatures around the set
point which will be designated as in-range. If the control temperature is in-range,
the in-range light will be illuminated. There are four possible values:
1 = +/- 0.5C (+/- 0.9F)
2 = +/- 1.0C (+/- 1.8F)
3 = +/- 1.5C (+/- 2.7F)
4 = +/- 2.0C (+/- 3.6F) - Factory Default
Cd31 Stagger Start Offset
Time (Seconds)
The stagger start offset time is the amount of time that the unit will delay at start-
up, thus allowing multiple units to stagger their control initiation when all units are
powered up together. The eight possible offset values are:
0 (Factory Default), 3, 6, 9, 12, 15, 18 or 21 seconds
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