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5. 0 Explanation for FAQ
5.1 Refrigerant oil mixture with liquid refrigerant will result in lower insulation resistance value and
higher leakage current readings.
Solution: It is recommended to operating the system for a brief time to redistribute the refrigerant through
the system.
5.2 During reclaiming refrigerant process, the suction pressure drop causes compressor to discharge
discontinuously, the check valve inside of compressor will open and shut repeatedly and make clatter.
But it will not affect reliability of the compressor.
1)
Although above mentioned clatter makes no affect on the reliability of the compressor, if the compressor
keeps operating under low suction pressure status, the motor winding and discharge temperature will
raise up rapidly.
2)
The running period with low suction pressure under 0MPa (G) should be less than 1 minute.
5.3 Reverse Phase Protector cannot protect the compressor from reverse rotation due to wrong
wiring internal of the A/C system.
1)
The function of Reverse Phase Protector is to protect the compressor from reverse rotation due to the
external wrong wiring into A/C system.
2)
See Table 5-1 for judgments on reverse rotation of compressor
Table 5-1 Judgments on reversal rotation of compressor
Item
Normal Rotation
Reverse Rotation
Discharge Tube Temp. Increasing rapidly
No obvious changes
Suction Tube Temp.
Decline
Slightly increasing
Discharge Pressure
Increasing rapidly
No obvious changes
Suction Pressure
Decline
No obvious changes
Vibration & Noise
Instant great before coming to steadily
Always great
Current
Normal
Over excess of nominal value
5.4 Compressor temporary halting due to internal motor protector trips.
1)
Internal motor protector working principle
The linebreak motor protector is the automatic reset device containing a snap action bimetal switch. In three
phase compressor it protects against secondary single phasing. The motor protector is designed to protect
against variety fault conditions such as failure to start, running overload and fan failure, locked rotor, abnormal
operation of contactor.
2)
Status after the internal protector trips
When internal protector tripping, the circuit will be open between each of 3-phase R-S-T. Under the case of
overheat of motor, the high temperature of compressor shell will be found.
