Carrier 68G5-105 Series Operation & Service Manual page 32

Table 3-3. Driver Display Panel Alarm Message Definition - Continued
ALARM
TITLE
NO.
A27 Low Pressure
Shutdown
A28 High Voltage
A29 Low Voltage
A31 EEPROM
CODE CODE NAME
P5 Suction Pressure
P6 Discharge Pressure
P20 Compressor Hours
High
P21 Compressor Hours
Low
P22 Evaporator Hours
High
P23 Evaporator Hours
Low
P30
Controller Software Controller Software
Version
P31
T-312
CAUSE
Low suction pressure. Check cause of low
Power 12 vdc source
voltage is greater than
17 vdc.
Power 12 vdc source
voltage is less than 10
vdc.
Memory failure.
Table 3-4. Parameter Codes
This value is the suction pressure measured by the suction pressure transduc-
er. If the sensor is shorted it will display CL If it is open circuited it will display
OP. NOTE: This value is not updated, it is the value at the time that the code
is accessed.
This value is the discharge pressure measured by the discharge pressure
transducer. If the sensor is shorted it will display "CL" and if it is open circuited
it will display "OP". NOTE: This value is not updated, it is the value at the time
that the code is accessed.
This is the number of hours of operation that the compressor has run with the
clutch energized. The reading is in thousands.
This is the number of hours of operation that the compressor has run with the
clutch energized. The reading is in hundreds, tens and ones.
This is the number (in thousands) of hours of operation with the evaporator
fans energized.
This is the number (in hundreds, tens and ones) of hours of operation with the
evaporator fans energized.
This is the software version of the logic board. The first two digits of the soft-
ware revision are displayed. Ex. Revision XXYY XX is displayed after P30.
This is the software version of the logic board. The second two digits of the
software revision are displayed. Ex. Revision XXYY YY is displayed after P31.
REMEDY
suction pressure. (Re-
fer to section 3.3.3.)
Check, repair or re-
place alternator.
Repair or replace
wiring or alternator.
Replace main micro-
processor at next ser-
vice stop.
DESCRIPTION
3-4
MICROPROCESSOR RESPONSE
If alarm has been activated three
times in 30-minutes, the clutch will
be de-energized until the alarm is
de-activated.
If alarm has been activated three
times in 30-minutes, de-energizes
the rest of the system unless heat is
required. Runs the main evaporator
fan at low speed until alarm is reset.
All microprocessor outputs are de-
energized.
All microprocessor outputs are de-
energized.
Modifies out of range values to their
default values.