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

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T-362 4–46
Tests P6-6 through P6-10 are conducted by changing status of each valve and comparing suction pressure
change and/or compressor current change with predetermined values. Tests will cause compressor and
condenser fans to cycle on and off as needed to generate the pressure required for individual pre-trip sub tests.
The compressor will start in order to build discharge pressure, followed by compressor pump down sequence. At
the conclusion of compressor pump down sequence, the compressor will shut down and the valve test will start.
P6-6 Economizer Valve Test
Passes if suction pressure increases a minimum of 4 psia when the valve opens for 15 seconds.
P6-7 Digital Unloader Valve Test
Passes if pressure and current changes are within 3 seconds of DUV switch signal and either the
pressure change or the current draw change is above 5 psi or above 1.5A, respectively.
P6-9 Liquid Injection Valve Test
(If equipped) Test passes if change of suction pressure is greater than 4 psia when the valve opens for
10 seconds. Otherwise, it fails.
P6-10 Electronic Expansion Valve Test
The test records the suction pressure during the open valve position and passes if the suction pressure
increase is above 3 psi when the valve opens for 10 seconds.
NOTE
P7-0 & P8 are included with “Auto 2 & Auto 3” only. P9-0 through P10 are included with “Auto2” only.
High Pressure Tests:
For the P7 tests, the unit is run at full capacity without condenser fan running to make sure
that the HPS opens and closes properly.
P7-0 High Pressure Switch (HPS) Opening Test
Test is skipped if sensed ambient temperature is less than 7.2°C (45°F), return air temperature is less
than -17.8°C (0°F), or the water pressure switch is open.
With the unit running, the condenser fan is turned off and a 900 second (15 minute) timer is started. The
right display shows Discharge Pressure if the sensor is configured and valid, else Discharge
Temperature. The unit needs to disable Discharge Pressure limit and enable Current Limit checks.
The test fails immediately if:
• Ambient Temperature Sensor invalid
• Composite Return Temperature Sensor invalid
• HPS is open
The test fails if:
• HPS fails to open before 900 seconds total test time.
• Evaporator or Compressor IP Alarm.
• Calculated Dome Temperature exceeds 137.78°C (280°F).
• Discharge pressure exceeds 370 psig.
• Compressor Current exceeds limits
The test passes if HPS opens within the 15 minute time limit.
P7-1 High Pressure Switch (HPS) Closing Test
If return temperature greater than -2.4°C, set setpoint to -5.0°C, else set setpoint to -30°C. Restart unit
according to normal startup logic. Run unit normally for 120 seconds.
The test passes if the high pressure switch closes within 75 seconds after end of Test 7-0, else the test
fails.
Test P7-0 must pass for this test to execute.
Table 4–6 Controller Pre-Trip Test Codes (Continued)