Troubleshooting; Self Diagnostics; System Alarms - Carrier CAPRI-280 Operation And Service Manual

3.1 SELF DIAGNOSTICS

Self tests are executed on power up during operation. Er-
rors, if any, will be indicated by the display and the unit will
not be allowed to operate. The display will indicate errors
Code
ER 1 Data Memory
ER 2 Program Memory
ER 3 A/D
ER 4 Communication Failure
ER 5 Program Memory

3.2 SYSTEM ALARMS

a. Alarm codes
Alarms will be displayed by "AXX", or "IXX" where "A"
indicates that the alarm is active and "I" indicates that the
alarm is inactive. If the auto key is pressed the display will
scroll through the three digit hour meter readings. If
multiple alarms are present the user can scroll through
each alarm by pressing the auto key. When the end of the
alarm list is reached the display will show "--- --- ---". If the
auto key is held down for five seconds while "--- --- ---" is
displayed all inactive alarms are cleared.
b. Activation
When an alarm becomes active they will be placed in an
alarm queue in the order at which they initiate unless the
T-283
SECTION 3

TROUBLESHOOTING

CAUTION
!
DO NOT UNDER ANY CIRCUMSTANCES
ATTEMPT TO SERVICE THE MICROPRO-
CESSOR. SHOULD A PROBLEM DEVELOP WITH
THE MICROPROCESSOR, REPLACE IT.
Table 3-1. Error Codes
NAME
Logic board data memory failure.
Logic board program memory failure.
A/D and multiplexer failure.
Failure in communication between the logic board and MDST.
Display program memory failure.
!
with the code ER-X (X is the error number). The error
codes can also be read by counting the number of times
that the status and alarm LED's flash simultaneously.
DESCRIPTION
alarm is already present. Each alarm recorded will also
have an evaporator hour meter reading corresponding to
the activation time. When an alarm becomes inactive a
status indicator in the alarm queue will change to indicate
that the alarm is inactive. If any alarms are active the fault
output will be energized.
c. Alarm queue
The alarm queue consist of 10 alarm locations. When the
alarm queue is full an alarm will be generated but not
stored to indicated this. When alarms are viewed this will
be the first alarm to be shown.
d. Alarm clear
The user may clear inactive alarms through the MDST
keypad or computer communications.
3-1