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1-19
Code 31 --- Current Limit
The current limit is the maximum current demand
allowed on any phase at any time. Limiting the unit’s
current (amperage) reduces the load on the mains power
and lowers the compressor discharge pressure. Whenever
this is desirable, the limit can be lowered. Note, however,
that capacity is also reduced. The five values are:
21 = Factory Default (15, 17, 19, 23)
Code 32 --- Dehumidification Control
This code activates the dehumidification control
mode of the system. Press the
Enter
key to toggle the
mode between “ON” and “OFF.” When the code is set to
ON, the control probe LED will flash ON and OFF every
second to indicate the mode is active. Code 32 is only
applicable to units with a humidistat.
1.13.5 Alarms
The alarm philosophy balances the protection of the
refrigeration unit and that of the refrigerated cargo. The
action taken when an error is detected always considers
the survival of the cargo. Rechecks are made to confirm
an error actually exists. Some alarms requiring
compressor shutdown have time delays before and after
to try to keep the compressor on line. An example is a low
main voltage. When the voltage drops over 20%, an
indication is given on the display, but the unit will
continue to run.
If a detectable problem is found to exist, the red
alarm light will illuminate and its alarm code will be
alternately displayed with the set point on the left display.
For software revision number 106 or greater, the red
alarm light will illuminate for “20 series” alarms only.
To determine if other alarms exist or have existed,
the alarm list must be accessed. The alarm list will store
up to eleven alarms in the sequence in which they
occurred. When accessing the alarm list, an “IA” or an
“AA” will appear to the left of the alarm code number.
The “IA” indicates an inactive alarm; one that has
occurred, but no longer exists. The “AA” indicates an
active alarm; one that is still indicating an improper
condition.
The codes in memory are displayed by pressing the
code select
key and then an arrow key until Code 00 is
displayed in the left window. “Strt” will be displayed in
the right window. Press the
Enter
key to enter this code.
Now press the
up arrow
key and the alarm codes will be
displayed on the right window in the sequence they
occurred.
To extinguish the alarm light, and in so doing remove
all alarms from the alarm list memory, press the
alarm
reset
key and within five seconds the
Enter
key. If an
active alarm has been corrected, the microprocessor may
not detect this until the unit has been turned OFF and
ON. The OFF and ON action will cause a retest of all
components.
Alarms TP00 and TP01 can only be cleared by first
trip starting the unit (simultaneously pressing the
trip
start
key and hours since
trip start
key) and then pressing
the
alarm reset
and
Enter
keys.
The controller must be in the “Normal Display Mode.”
(ie., Set point and control Probe Display) and all alarms
must be inactive to clear the alarm light and queue.
Alarm 20 --- Control Circuit Fuse
Alarm 20 is triggered by the control circuit fuse
opening and will cause the software shutdown of all
control units. This alarm will remain active until the
6-amp fuse is replaced.
Alarm 21 --- Evaporator Fan Motor
Alarm 21 is triggered by the opening of the
evaporator motor internal protector. This alarm will
disable all control units until the motor protector resets.
Alarm 22 --- Auto Transformer
Alarm 22 is triggered by the auto transformer
internal protector opening, and will result in the disabling
of all control units except the evaporator fans. The alarm
will stay active until the transformer protector resets.
Alarm 23 --- Compressor Motor
Alarm 23 is triggered by the opening of the
compressor motor internal protector. This alarm will
disable all control units except for the evaporator fans
and will remain active until the motor protector resets.
Table 1-5. Alarm Indications
ALARM NO.
ALARM DESCRIPTION
AL20
Control Circuit Fuse Open
AL21
Evaporator Fan Motor Internal Protector
AL22
Auto Transformer Internal Protector
AL23
Compressor Motor Internal Protector
AL24
Condenser Fan Motor Internal Protector
AL25
Compressor High Pressure Limit Safety
AL26
All Supply and Return Air Sensor Failure
AL27
Probe Circuit Calibration Failure
AL51
Alarm List Failure
AL52
Alarm List Full
AL53
Main Voltage Sensor Failure
AL54
Primary Supply Air Sensor Failure
AL55
Secondary Supply Air Sensor Failure
AL56
Primary Return Air Sensor Failure
D
AL57
Secondary Return Air Sensor Failure
AL58
Ambient Temperature Sensor Failure
AL59
Heat Termination Thermostat
Failure
AL60
Defrost Termination Thermostat Failure
(Closed)
AL61
Defrost Termination Thermostat Failure
(Open)
AL62
Heaters Failure
AL63
Compressor Motor Failure
D
AL64
DataCORDER Low Battery
AL65
Current Over Limit
D
TP00
Approaching DataCORDER Memory
Overwrite
D
TP01
DataCORDER Overwriting Data
ERR #
Internal Microprocessor Failure
LO
Low Main Voltage (More than 20%)
D
= Alarms that are NOT APPLICABLE for some
units
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