Oct 14, 2020
How can the inverter "long life"
Inverter is one of the most popular electrical equipment in the new century and has attracted the attention of various industries. Although frequency converters have entered our lives, problems such as failures will always occur, and many users need to pay attention to maintenance skills in use.
To what extent can the inverter "long life"?
1. Correct wiring and parameter settings. Before installing the inverter, be sure to read its manual, master its usage, precautions and wiring; after installation, set the parameters correctly according to the use.
2. V/F control belongs to constant torque adjustment. The vector control increases the output torque of the motor in proportion to the square of the voltage, thereby improving the output torque of the motor at low speed.
3. The problem of external control signal failure. Generally, there are several situations: incorrect signal mode, wrong terminal wiring, incorrect parameter settings or problems with external signals.
4. The ambient temperature has a great influence on the service life of the inverter. Every 10℃ of ambient temperature will halve the life of the inverter, so the surrounding ambient temperature and the problem of inverter heat dissipation must be resolved.
5. Pay attention to the relationship between speed and head. The selection of the motor and its optimal working period are more important issues. If the inverter runs below 5HZ for a long time, the motor heating becomes a prominent problem.
6. If the system adopts power frequency/frequency conversion switching mode, the interlock between the power frequency output and the variable frequency output must be reliable. In addition, the inverter must be stopped when starting and stopping the pump and the power frequency/frequency conversion switch before operating the contactor. Since the contact adhesion and the extinguishment of the arc of the large-capacity contactor require a certain amount of time, the above-mentioned switching sequence and time should be considered thoroughly.
7. The difference between overcurrent trip and overload trip. Overcurrent is mainly used to protect the frequency converter, and overload is mainly used to protect the motor. Because the capacity of the inverter sometimes needs to be increased by one or two gears than the capacity of the motor, in this case, the inverter may not necessarily overcurrent when the motor is overloaded. The overload protection is performed by the electronic thermal protection function inside the inverter. When the electronic thermal protection is preset, the "current draw ratio" should be accurately preset, that is, the percentage of the ratio of the rated current of the motor to the rated current of the inverter.