Carrier PrimeLINE 69NT40-561-200, Руководство по эксплуатации и обслуживанию

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4–47 T-362
Perishable Mode Tests: In order for P8 tests to execute, Pre-trip tests P7-0 and P7-1 must have passed or have
been skipped.
P8-0 Perishable Mode Test
If the control temperature is below 15.6°C, the setpoint is changed to 15.6°C, and a 180 Minute timer is
started. The control will then be placed in the equivalent of normal heating. If the control temperature is
above 15.6°C. at the start of the test, then the test proceeds immediately to test 8-1. While in test 8-0 the
right display will show the value of the control temperature.
The test fails if the 180 Minute timer expires before the control temperature reaches setpoint - 0.3°C. If
the test fails, it will not auto-repeat. There is no pass display for this test. Once the control temperature
reaches setpoint, the test proceeds to test 8-1.
P8-1 Perishable Mode Pull Down Test / CO2 Sensor Calibration
Control temperature must be at least 15.6°C (60°F).
The setpoint is changed to 0°C (32°F), and a 180-minute timer is started. The left display will read “P8-
1,” the right display will show the supply air temperature. The unit will then start to pull down the
temperature to the 0°C setpoint.
The test passes if the container temperature reaches setpoint before the 180-minute timer expires.
On units where the CO
2
Sensor Status indicates that a CO
2
sensor is present, calibration of the CO
2
sensor will be attempted during P8-1. Once P8-1 begins, calibration will be attempted when the supply
temperature goes below 5°C. If the CO
2
sensor voltage reads within the 0.95 <>1.15Vdc range before
the end of P8-1, the sensor will be calibrated by holding the CO
2
zero line low for 4 seconds. Once
calibration is performed, the sensor voltage will be verified to make sure it is in the 0.95 to 1.05 Vdc range.
If the voltage is not within this range, CO
2
sensor calibration fails.
P8-2 Perishable Mode Maintain Temperature Test
Test P8-1 must pass for P8-2 to execute.
A fifteen minute timer is started, and the system will attempt to minimize control temperature error (supply
temperature minus setpoint) until the timer expires. The control temperature will be sampled each minute
starting at the beginning of P8-2.
During P8-2, the left display will read “P8-2,” and the right display will show the supply air temperature.
When the test is completed, the average control temperature error will be compared to the pass/fail
criteria.
Test passes if the average temperature error is /- 1.0°C.
Test fails if the average temperature error is greater than +/- 1.0°C, or if the DataCORDER supply
temperature probe is invalid. If the test fails, the control probe temperature will be recorded as -50.0°C.
DTT Close and Open Test: For the P9 tests, the DTT in this control is not a physical device, with actual metallic
contacts, it is a software function that acts similar to a thermostat. Using various temperature inputs, the DTT
function determines whether a thermostat mounted on the Evaporator Coil would have OPEN or CLOSED
contacts. Primarily, the DTT function operates based on the temperature reading from the Defrost Termination
Sensor.
P9-0 DTT Closed and Open Test
During P9-0 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. This step may
not have to be executed. 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.
Test fails if The DTT is not considered closed after the 30 minutes of full cooling. Or, if the HTT opens
when DTT is considered closed or if return air temperature rises above 48°C (120°F).
Test passes if the DTT is considered open within the 2 hour heat cycle time limit.
Table 4–6 Controller Pre-Trip Test Codes (Continued)