Due to the structure of the inverter itself, the normal operation of the inverter is greatly affected by the external working environment. To ensure that the external working environment is within a certain range, the external environment maintenance and frequency converter preventive are performed through the timing. Maintenance inspection ensures that the working environment of the inverter is optimized, so that early detection of invisible faults and early processing can reduce the serious failure probability of the inverter and reduce the downtime of the equipment. According to our company's many years of field experience, it is summarized as follows:
1. Ambient temperature: When the temperature is too high and the temperature changes greatly, the inside of the inverter is prone to condensation. Especially when the equipment is powered off again after the machine is shut down, because the inverter is powered off due to shutdown, its temperature is cooled and the air is in the air. When the water is cooled and attached to the circuit board, the casing, and the bronze plate, the insulation performance will be greatly reduced, and even a short circuit accident may occur; if the internal dust of the inverter is accumulated more and the maintenance is not timely, the inverter The failure rate will be very high, and even the possibility of multiple devices being damaged at the same time directly leads to the suspension of production.
2. Inverter working temperature: The internal frequency of the inverter is a high-power electronic component, which is highly susceptible to the working temperature. If the temperature is too high or too low, the electronic components will work abnormally. To ensure the normal operation of the inverter, the inverter must be guaranteed. The electric cabinet has a good ventilation and heat dissipation system, and the air inlet and outlet of the electric cabinet are not blocked, so that the ventilation fan works normally.
3. Vibration and shock: Because the internal electrical connection of the inverter is usually screwed, the cable between the boards is also a connector. If the inverter is vibrating, it may cause poor contact in these parts.
4. Dust: The inverter is not suitable for working under dusty conditions. Because the inverter itself relies on forced air cooling, the dust is more likely to cause the inverter cooling fan to block, even burning the fan, the dust will block the heat. The air duct causes the heat to be discharged in time. The inverter does not get good heat dissipation, and its own working temperature rises, which will cause the inverter to overheat alarm and stop. In severe cases, the inverter will be damaged directly.
5. Power supply: The power supply abnormality is roughly divided into the following three types, namely, phase loss, low voltage, and over voltage. These three conditions will directly cause the inverter to not work. The main cause of these abnormal phenomena is mostly caused by transmission lines. Sometimes, due to short circuit to ground, short circuit between phases, or start and stop of large power equipment in the same power supply system, in addition to voltage fluctuations, some power grids or units that generate electricity by themselves may also experience frequency fluctuations, and these phenomena are sometimes in a short time. Repeatedly, in order to ensure the normal operation of the equipment, the power supply of the inverter is also required.
6. Lightning strikes and inductive lightning: The lightning voltage formed by lightning strikes or induced lightning strikes. In some seasons, lightning is more, and lightning is transmitted to the power grid, which will cause damage to the inverter. Therefore, it is necessary to check the lightning protection device to ensure that the lightning protection device plays an important role. In addition, when the power system has a vacuum circuit breaker on the primary side, short circuit opening and closing will generate a high surge voltage. In order to prevent overvoltage damage caused by the surge voltage, it is usually necessary to apply a absorbing device such as a varistor at the input end of the inverter. Vacuum circuit breakers should be added to the RC surge absorber. If there is a vacuum circuit breaker on the primary side of the transformer, the inverter should be disconnected before the vacuum circuit breaker is operated at the control timing. The operating electrician must have the operational specifications in this respect.