Operating instructions

TM 11574A-OI
2-37
Table 2-8 Controller Pre-Trip Test Codes - Continued
Code
No.
TITLE DESCRIPTION
Note, this test is skipped if the unit does NOT have:
A compressor discharge sensor (CPDS).
A discharge pressure transducer (DPT).
Condenser pressure transducer (CPT).
In addition, this test is skipped if:
The sensed ambient temperature is less than 45 F (7 C).
The return air temperature is less than 0F (-17.8 C).
Pass/Fail Criteria: Under conditions of the above NOTE; the test immediately
fails if the following inputs are sensed to be invalid:
Compressor discharge sensor (CPDS).
Discharge pressure transducer (DPT).
Condenser pressure transducer (CPT).
OR, if any one of the following inputs are sensed to be invalid:
Return temperature sensor (RTS).
Ambient sensor (AMBS).
P7-0
High Pressure
Switch Closed
(Continued)
In addition, the test will fail if:
The high pressure switch (HPS) fails to open within 15 minutes.
The discharge temperature exceeds 280 F (138 C).
The discharge temperature is less than or equal to ambient temperature plus
9 F (5 C).
The condenser pressure transducer (CPT) or discharge pressure transducer
(DPT) pressure exceeds 390 psig (27.42 kg/cm
2).
P7-1
High Pressure
Switch Open
Requirements: Test P7-0 must pass for this test to execute. Setup: The con-
denser fan is started and a 60 second timer is started.
Pass/Fail Criteria: Passes the test if the high pressure switch (HPS) closes
within the 60 second time limit, otherwise, it fails.
P8-0
Perishable Mode
Heat Test
Setup: If the container temperature is below 60 F (15.6 C), the set point is
changed to 60 F (15.6 C) and a 60 minute timer is started. The left display will
read “P8-0.” The control will then heat the container until 60 F (15.6 C) is
reached. If the container temperature is above 60 F (15.6 C) at the start of the
test, then the test proceeds immediately to test P8-1 and the left display will
change to “P8-1.” Pass/Fail Criteria: The test fails if the 180 minute timer
expires before the control temperature reaches set point. The display will read
“P8-0,” “FAIL.”
P8-1
Perishable Mode
Pull Down Test
Requirements: Control temperature must be at least 60 F (15.6 C).
Setup: The set point is changed to 32 F (0 C), and a 180 minute timer is started.
The left display will read “P8-1,” the right display will show the supply air temper-
ature. The unit will then start to pull down the temperature to the 32 F (0 C) set
point. Pass/Fail Criteria: The test passes if the container temperature reaches
set point before the 180 minute timer expires.