1. Cause of overload of frequency converter.
1) the main feature of heavy mechanical load is the heating of the motor, which can be found by reading the running current from the display screen.
3) the unbalanced three-phase voltage causes the operating current of a certain phase to be too large, resulting in load power jump. It is characterized by the asymmetrical heat generated by the motor, which will not be found when the operating current is loaded from the display screen.
3) the internal current detection part of the misoperation frequency converter fails, and the detected current signal is too large, resulting in tripping.
2. Overload troubleshooting method of Inverter.
1) check whether the motor is hot.
2) check whether the three-phase voltage on the motor side is balanced.
3) check whether the frequency converter is malfunctioning.
When the cause is not found after the above inspection, it should be checked to see if it is a misoperation. The judgment method is to use the ammeter to measure the output current of the frequency converter under light load or no load, and compare it with the running current displayed on the display screen. If the current reading displayed on the display screen is much larger than the actual measured current, the error in the internal current measurement part of the frequency converter is very large, and "overload" tripping may be a misoperation.