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T-317
4-5
PRE-TRIP SELECTION MENU
Auto or Auto 1 Auto 2
Auto 3
P, P1, P2, P3,
P4, P5, P6,
rSLts
P, P1, P2, P3,
P4, P5, P6, P7,
P8, P9, P10,
rSLts
P, P1, P2, P3,
P4, P5, P6, P7,
P8, rSLts
A detailed description of the pre-trip test codes is listed
in Table 3-7, page 3-21. If no selection is made, the
pre-trip menu selection process will terminate
automatically. However, dehumidification and bulb
mode must be reactivated manually if required.
Scrolling down to the “rSLts” code and pressing ENTER
will allow the user to scroll through the results of the last
pre--trip testing run. If no pre--testing has been run (or an
individual test has not been run) since the unit was
powered up “--------” will be displayed.
To start a pre--trip test, do the following:
NOTE
1. Prior to starting tests, verify that unit
voltage (Function Code Cd 07) is within
tolerance and unit amperage draw
(Function Codes Cd04, Cd05, Cd06) is
within expected limits. Otherwise, tests
may fail incorrectly.
2. All alarms must be rectified and cleared
before starting tests.
3.
Pre-trip diagnosis may also be initiated via
communications. The operation is the
same as for the key pad initiation described
below except that should a test fail, the
pre-trip mode will automatically terminate.
When initiated via communications, a test
may not be interrupted with an arrow key,
but the pre-trip mode can be terminated
with the PRE-TRIP key.
a. Press the PRE-TRIP key. This accesses a test selec-
tion menu.
b. TO RUN AN AUTOMATIC TEST: Scroll through the
selections by pressing the UP ARROW or DOWN
ARROW keys to display AUTO, AUTO 2 or AUTO 3
as desired and then press the ENTER key.
1. The unit will execute the series of tests without any
need for direct user interface. These tests vary in
length, depending on the component under test.
2. While tests are running, “P#-#” will appear on the left
display, where the #’s indicate the test number and
sub-test. The right display will show a countdown time
in minutes and seconds, indicating how much time
there is left remaining in the test.
CAUTION
When a failure occurs during automatic
testing the unit will suspend operation
awaiting operator intervention.
When an automatic test fails, it will be repeated once .
A repeated test failure will cause “FAIL” to be shown
on the right display, with the corresponding test num-
ber to the left. The user may then press the DOWN
ARROW to repeat the test, the UP ARROW to skip to
the next test or the PRE--TRIP key to terminate test-
ing. The unit will wait indefinitely, until the user manu-
ally enters a command.
CAUTION
When Pre--Trip test Auto 2 runs to comple-
tion without being interrupted, the unit will
terminate pre-trip and display “Auto 2”
“end.” The unit will suspend operation until
the user depresses the ENTER key!
When an Auto test runs to completion without a failu-
re, the unit will exit the pre-trip mode, and return to
normal control operation. If configuration variable
CnF42 is set to IN, a datacorder trip start will be en-
tered. If CnF42 is set to OUT, the trip start will not be
entered. However, dehumidification and bulb mode
must be reactivated manually if required.
c. TO RUN AN INDIVIDUAL TEST: Scroll through the
selections by pressing the UP ARROW or DOWN
ARROW keys to display an individual test code.
Pressing ENTER when the desired test code is dis-
played.
1. Individually selected tests, other than the LED/Dis-
play test, will perform the operations necessary to
verify the operation of the component. At the conclu-
sion, PASS or FAIL will be displayed. This message
will remain displayed for up to three minutes, during
which time a user may select another test. If the
three minute time period expires, the unit will termi-
nate pre-trip and return to control mode operation.
2. While the tests are being executed, the user may ter-
minate the pre-trip diagnostics by pressing and hold-
ing the PRE-TRIP key. The unit will then resume nor-
mal operation. If the user decides to terminate a test
but remain at the test selection menu, the user may
press the UP ARROW key. When this is done all test
outputs will be de-energized and the test selection
menu will be displayed.
3. Throughout the duration of any pre-trip test except
the P-7 high pressure switch tests, the current and
pressure limiting processes are active .
d. Pre-Trip Test Results
At the end of the pre-trip test selection menu, the
message “P,” “rSLts” (pre--trip results) will be displayed.
Pressing the ENTER key will allow the user to see the
results for all subtests (i.e., 1-0, 1-1, etc). The results will
be displayed as “PASS” or “FAIL” for all the tests run to
completion since power up. If a test has not been run
since power up, “
-- -- -- -- --
” will be displayed. Once all
pre--test activity is completed, dehumidification and
bulb mode must be reactivated manually if required.
4.9 OBSERVE UNIT OPERATION
4.9.1 Crankcase Heater
When the crankcase heater is installed, it will be
operational whenever the compressor is off and there is
power to the unit. The heater is connected to a set of
normally closed auxiliary contacts on the compressor
contactor.