Method for detecting frequency converter faults with a multimeter
Sound level meter is the most basic instrument for measuring noise. It belongs to an electronic In the daily maintenance process of frequency converters, various problems are often encountered, such as peripheral circuit problems, parameter settings, or mechanical failures. If the frequency converter malfunctions, how to determine which part of the problem it is, will be briefly introduced here.
1. The damage of rectifier modules is generally caused by grid voltage or internal short circuits. Replace the rectifier bridge after eliminating internal short circuits. When dealing with faults on site, it is important to focus on checking the user's power grid situation, such as the voltage of the power grid and the presence of equipment such as welding machines that pollute the power grid.
2. Damage to the inverter module is generally caused by motor or cable damage and drive circuit faults. After repairing the driver circuit, replace the module when the driver waveform is in good condition. After replacing the driver board in on-site service, it is also necessary to pay attention to checking the motor and connecting cables. Run the frequency converter after confirming that there are no faults.
3. The lack of display when powered on is generally caused by damage to the switching power supply or soft charging circuit, resulting in no DC power in the DC circuit. If the starting resistor is damaged, it may also be due to panel damage.
4. Overvoltage or undervoltage displayed after power on is generally caused by input phase loss, circuit aging, and moisture on the circuit board. Identify its voltage detection circuit and detection points, and replace damaged components.
5. Overcurrent or ground short circuit displayed after power on is generally due to damage to the current detection circuit. Such as Hall elements, operational amplifiers, etc.
6. The startup display overcurrent is generally caused by damage to the driving circuit or inverter module.
7. The no-load output voltage is normal, but it shows overload or overcurrent after being loaded. This situation is generally caused by improper parameter settings or aging of the driving circuit, module damage.
