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The novice can solve the frequency converter common fault diagnosis and processing.(5)
- May 28, 2018 -

1.4 damage to the fan

1.4.1 damage judgment of fan

(1) measure whether the fan power supply voltage is normal. If the fan power supply is abnormal, first repair the fan power supply.

(2) confirm that if the fan does not turn or slow down after the fan power is normal, the fan has been damaged and needs to be replaced.

1.4.2 cause of damage

(1) the fan itself quality is bad, lines burned, local short circuit, until the electronic circuit of the fan is damaged, or the fan wire break, mechanical stuck, oil bearing dry aging, plastic deformation.

(2) poor environment, including water vapor, condensation, corrosive gas, blockage of dirt, and deformation of plastics due to high temperature.

1.4.3 fan replacement

(1) it is better to choose the original model or the one with better performance than the original model when replacing the new fan. The fan of the same size includes many kinds of air volume and air pressure.

(2) there are many cases when the fan is disassembled to pull the internal motor core of the frequency converter, and records and marks should be made in the disassembly to prevent errors when it is put back to the original.Some designs have taken full account of the replacement convenience, at this time to see clearly, do not blindly large tear down, big move.

(3) when the fan is installing screws, the torque should be appropriate, and the plastic parts should not be deformed or broken due to over-tightening, nor loose due to vibration.The blades of the fan shall not touch the hood, nor shall the reverse fan be installed.

(4) when selecting the fan, it is advisable to pay attention to that the fan bearing is ball bearing, and the mechanical life of oil-bearing is short.For the simple bearing life, the fan life will be 5 yao 10 times higher when using ball bearing.

(5) the fan is installed in the air outlet to withstand high temperature air flow, and its air blade is made of metal or temperature-resistant plastic, and shall not use inferior plastic to avoid deformation.

(6) the power supply shall be properly connected, and the rotor blade shall not rub against the conductor. After installation, it shall be electrified and tested.

(7) it is very important to clean up the blockage of air duct and radiator. Many frequency converters are damaged or protected by overheating due to the blockage of air duct.

1.5 damage of switching power supply

1.5.1 judgment of switch power failure

(1) there is an input voltage, but no switching power output voltage, or the output voltage is obviously wrong.

(2) the switch power supply switch tube, transformers, PCB peripheral components, especially the overvoltage absorbing components have appearance visible yellow, burning, burning of the multimeter measuring elements such as switch tube is damaged.

(3) switch transformer enameled wire used at high temperature for a long time, appear yellow, burnt odour, breakdown, between transformer winding transformer winding especially high tension line break line, skeleton deformation and jump arc trace.

1.5.2 find the cause of switch power failure

(1) the leakage of the switching power transformer itself is too large.When running a winding leakage inductance of the overvoltage caused great energy, this energy is absorbed elements (resistance capacity components, voltage regulator tube, transient voltage suppression diode) absorption occurs when serious overload, over time to absorb the component is damaged.

All these reasons and the efficiency of switch power supply will be reduced, the switch tube and switch transformer fever severely, and high peak reverse voltage appears on the switch tube, led switch tube damage and the damage of transformer, special transformer, switch tube in an airtight case, absorb with resistance, voltage regulator tube or the temperature of the transient voltage suppression diode will be very high.

(2) the transformer wire breaks due to oxidation and flux corrosion.

(3) the life of components themselves, especially switch tubes and switching integrated circuits, are more vulnerable to damage due to the large current voltage burden.

(4) poor environment, insulation damage caused by dust, water vapor, etc.

1.5.3 repair of switching power supply

(1) the switch power supply because of the local high temperature has yellow PCB depth carbonation or damage when printing line, PCB insulation and, copper-clad wires cannot use, can only change the PCB as a whole.

(2) find out the damaged components after changing a new component, component model should be consistent with the original models, when can't consistent, want to make sure the component power, switch frequency, voltage and size can be installed, and insulation distance must be maintained and the surrounding components.

(3) after it is believed to have been repaired, it shall be checked by electricity.Electricity should not make the whole inverter power by only to have that part of the switch of the transformer, i.e. on the power supply side of the switch transformer energizing, check whether the work is normal, the secondary voltage is correct, change the power supply side of the voltage in the + 15% - 20 change range of the output voltage should be basically the same.