1. Maintenance items and scope:
Daily maintenance and maintenance of inverter
Due to the influence of environmental temperature, humidity, dust and vibration, it will lead to the aging of the internal components of the inverter, resulting in the potential failure of the inverter or reducing the service life of the inverter. Therefore, it is necessary to carry out routine and regular maintenance and maintenance of the frequency converter.
2. Daily inspection items:
1. Whether the sound changes abnormally during the operation of the motor.
2. Whether there is vibration during the operation of the motor.
3. Whether the installation environment of the inverter has changed.
4. Whether the inverter cooling fan is working normally.
5. Whether the inverter is overheated.
3. Daily cleaning:
1. The inverter should always be kept in a clean state.
2. Effectively remove the dust on the surface of the inverter and prevent the dust from entering the inverter, especially the metal dust.
3. Effectively remove the grease and dirt of the inverter cooling fan.
Fourth, regular inspection items:
1. Check the air duct and clean it regularly.
2. Check whether the screws are loose.
3. Check the corrosion of the inverter.
4. Check whether the terminal blocks are subject to arc marks.
5. Main circuit insulation test.
5. Replacement of wearing parts of inverter:
The vulnerable components of the inverter include cooling fans and electrolytic capacitors for filtering, and their life is closely related to the environment and maintenance status of use.
The user can determine the replacement period based on the operating time.
1. Cooling fan
Possible causes of damage: bearing wear, aging of blades.
Criteria: whether there are cracks in the fan blades, etc., and whether there is abnormal vibration sound when the sound is turned on.
2. Filter electrolytic capacitors
Possible causes of damage: poor input power quality, high ambient temperature, frequent load jumps, and electrolyte aging.
Judging criteria: whether there is liquid leakage, whether the safety valve has protruded, measurement of electrostatic capacitance, measurement of insulation resistance.
6. Daily maintenance items:
1. Measure the insulation of the inverter and check whether the main power supply screws are loose
2. Clean the heat sink and check whether the cooling fan is obstructing the operation
3. Clean up the dust and oil stains in the air duct to ensure that the heat dissipation channel of the inverter is not blocked
4. Whether there is abnormal noise in operation, whether the fan blade is cracked, and whether the installation screws are loose
5. IGBT temperature measurement of frequency converter
6. Control power measurement
7. Current harmonic analysis
8. Motor current measurement, three-phase balance detection
9. The output voltage of the inverter is measured, and the three-phase balance is detected
10. Motor insulation test (be sure to remove the cable and measure the terminal, there is a risk of damaging the IGBT by shaking the meter)
11. Motor running temperature monitoring
12. Measure the temperature of the motor cable
7. Preventive maintenance items:
1. Clean up the dust of the PCB circuit board, test the aging degree of each circuit, and spray the conformal paint partly (if necessary, it is recommended that the customer replace the aging circuit board)
2. IGBT performance test, re-apply thermal grease (if necessary, it is recommended that customers replace the aging IGBT)
3. Main capacitor capacity measurement, insulation resistance measurement, withstand voltage test (if necessary, it is recommended that customers replace the aging capacitor)
4. Replace the cooling fan, usually it is recommended to replace it every 2 years;
5. Check whether the contacts of the main circuit contactor are defective and whether the mechanical parts are smooth (it is recommended that customers replace them if necessary)
6. Copper plate to ground insulation test of main circuit, insulation test between copper plates, screw fastening;
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