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3-24
T-296
Table 3-7 Controller Pre-Trip Test Codes (Sheet 4 of 4)
P8-2
Perishable Mode
Maintain Tempera-
ture Test
Requirements:
Test P8-1 must pass for this test to execute.
Setup:
The left display will read “P8-2,” and the right display will show the supply
air temperature. A 60 minute timer is started. The unit will be required to main-
tain the 0
°
C temperature to or -- 0.5
_
C (0.9
_
F) of set point until a Data-
CORDER recording is executed. The recorder supply probe temperature running
total (and its associated readings counter) will be zeroed out for the remainder of
the recording period at the start of this test, so that the actual value recorded in
the DataCORDER will be an average of only this test’s results. Once a recording
interval is complete, the average recorder supply temperature will be recorded in
the DataCORDER, as well as stored in memory for use in applying the test pass/
fail criteria.
Pass/Fail Criteria:
If the recorded temperature is /-- 0.5
_
C. of set point
from test start to DataCORDER recording, the test passes. If the average tem-
perature is outside of the tolerance range at the recording, the test fails.
P9-0
Defrost Test
Setup:
The defrost temperature sensor (DTS) reading will be displayed on the
left display. The right display will show the supply air temperature. The unit will
run FULL COOL for 30 minutes maximum until the DTT is considered closed.
Once the DTT is considered closed, the unit simulates defrost by running the
heaters for up to two hours, or until the DTT is considered open.
Pass/Fail Criteria:
The test fails if: the DTT is not considered closed after the 30
minutes of full cooling, HTT opens when DTT is considered closed or if return air
temperature rises above 248
_
C (120
_
F).
P10-0
Frozen Mode
Setup Test
S
etup:
After completion of the defrost test, the testing proceeds directly to test
P10--1 if the container temperature is above 7
_
C (45
_
F). If the container temper-
ature is below 7
_
C, a 180 minute timer will be started, the set point will be set to
7
_
C and the control will be placed in normal heat. The left display will read
“P10--0” and the unit will continue in operation until the temperature is raised to
set point.
Pass/Fail Criteria:
If the temperature does not reach set point(less --0.3
_
C or
6.7 F) before the timer times out display will read “P100,” “FAIL”. The test will not
auto--repeat.
P10-1
Frozen Mode (Pull
Down) Test
Setup:
When the container temperature is greater than or equal to the 7.2
°
C
(45
_
F) set point which was set in the frozen mode heat test, the left display will
read “P10--1” and the right display will show the return air temperature. The set
point will then be changed to --17.7
_
C (0
_
F). The unit will then have a maximum
of three hours to pull the container temperature down to the --17.7
°
C set point.
Pass/Fail Criteria:
If this occurs within the three hour time limit, the test passes.
If pulldown is not completed within the three hour time, the test fails.
P10-2
Frozen Mode Main-
tain Temperature
Test
Setup:
After the unit has successfully completed frozen pulldown test, the left
display will read “P10--2” and the right display will show return air temperature.
The unit will then be required to maintain --17.7
°
C (0
_
F) temperature /--
0.5
_
C (0.9
_
F) of set point until a DataCORDER recording is executed. The
recorder return probe temperature running total (and its associated counter) will
be zeroed for the remainder of the recording period at the start of this test, so
that the actual recorded value will be an average of only this test’s results. Once
the recording interval is complete, the average return temperature will be
recorded in the DataCORDER, and stored in memory for use in applying the test
pass/fail criteria.
Pass/Fail Criteria:
If the recorded temperature is /-- 0.5
_
C of set point
from test start to DataCORDER recording, the test passes. If temperature is out-
side of the tolerance range at the DataCORDER recording, the test fails.
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