The main function of the frequency converter is to adjust the power of the motor and realize variable speed operation of the motor to achieve the purpose of saving power. At the same time, the function of the frequency converter can reduce the voltage fluctuation of the power line, because the voltage drop will cause the voltage-sensitive equipment in the same power supply network to malfunction, trip or work abnormally. After using the frequency converter, the function of the frequency converter can be gradually started at zero frequency and zero voltage, which can eliminate the voltage drop to the greatest extent and give greater advantage.
Misunderstandings that should be avoided when using frequency converters:
1. Do not install the frequency converter on equipment with vibration, because the main circuit connecting screws in the frequency converter will easily loosen. Many frequency converters have been damaged due to this reason.
2. Wiring problem: It is best to connect the input end of the frequency converter to an air connection. The value of the protection current should not be too large to prevent serious burnout in the event of a short circuit. The "N" terminal must not be connected to ground. The control line should not be too long. Because this makes the control board susceptible to electromagnetic wave interference and malfunction, which can also cause damage to the control board, it is best to use shielded wires longer than 2 meters. Do not install a contactor with high current and frequent operation next to the frequency converter, because it will interfere greatly with the frequency converter and often cause the frequency converter to malfunction (display various faults).
3. For frequency converters that often need to make emergency stops, it is best not to rely on the frequency converter itself for braking, but to add an additional braking unit or use mechanical braking. Otherwise, the frequency converter is often impacted by the motor's counter electromotive force, and the failure rate will be greatly increased.
4. If the frequency converter often runs at low speed below 15Hz, the motor must be equipped with an additional cooling fan.
5. Dust and moisture are fatal killers of frequency converters. It is best to install the inverter in an air-conditioned room or in an electrical cabinet with a dust filter. The dust on the circuit board and radiator must be cleaned regularly. If the inverter has been shut down for a period of time, it is best to blow it with a hair dryer before powering on. circuit board.
6. When the cooling fan of the frequency converter is broken, it will issue an overheating protection. When the fan makes noise, it should be replaced.
7. Some factories use generators to generate power. The voltage is unstable and the inverters are often damaged. The generators are equipped with voltage stabilizing or overvoltage protection devices, which have good results.
8. Lightning protection is also very important. Although it rarely happens, when the inverter is struck by lightning, it will be severely damaged. The frequency converter with constant pressure water supply is easily struck by lightning because it has a lightning-inducing water pipe extending into the sky.
9. In order to prevent electromagnetic wave interference, it is best to use shielded wires for the input, output, and control lines of the frequency converter. The wiring method of the shielding layer cannot be wrong, otherwise the effect will be opposite. If possible, use iron pipes to cover them, install filters, and lower the carrier frequency. We found that if the switching tube of the inverter switching power supply is a field effect tube (such as K series), the interference will be greater.
10. When the inverter breaks down, do not leave it to someone with no maintenance experience to repair it! Otherwise, it may get worse with repairs! Sometimes the fuse is about to blow, so be sure to check if there is a problem. Some electricians are inexperienced, so install a good one immediately. Fast fuse ("cannot be replaced by copper wire") will cause the inverter to burn out more severely. According to our experience, if it fuses quickly, there is usually something wrong with the module, but if the module is bad, it will fuse quickly and it will not necessarily break. Many inverter power modules and rectifier modules are interchangeable.
