Inverter technology is widely used in various industries, from manufacturing to HVAC systems. However, like any other electrical equipment, inverters need to be handled with caution to ensure their safe and efficient operation. This article discusses the precautions that should be taken when using inverters, including considerations for the physical and electrical environment, grounding, and lightning protection. By following these guidelines, users can avoid potential hazards and extend the lifespan of their inverters.

Precautions for Inverter Use

1. Physical environment

1) Working temperature. The inside of the inverter is a high-power electronic component, which is easily affected by the working temperature. The product generally requires 0~55, but in order to ensure safe and reliable operation, it should be considered to leave room for use, and it is best to control it below 40. In the control box, the inverter should generally be installed on the upper part of the box, and strictly abide by the installation requirements in the product manual. It is absolutely not allowed to install heating elements or components that are prone to heat close to the bottom of the inverter.

2) Ambient temperature. When the temperature is too high and the temperature changes greatly, condensation is prone to occur inside the inverter, and its insulation performance will be greatly reduced, and even short-circuit accidents may occur. If necessary, a desiccant and a heater must be added to the box.

3) Corrosive gas. If the concentration of corrosive gas is high in the use environment, it will not only corrode the lead wires of components, printed circuit boards, etc., but also accelerate the aging of plastic devices and reduce the insulation performance. In this case, the control box should be made into a closed structure. , and ventilate.

4) Vibration and shock. When the control cabinet equipped with the frequency converter is subjected to mechanical vibration and shock, it will cause poor electrical contact. At this time, in addition to improving the mechanical strength of the control cabinet and keeping it away from vibration sources and shock sources, anti-seismic rubber pads should be used to fix vibration-generating components such as the external and internal electromagnetic switches of the control cabinet. After the equipment has been in operation for a period of time, it should be inspected and maintained.

2. Electrical environment

1) Prevent electromagnetic wave interference. Due to the rectification and frequency conversion during the operation of the frequency converter, a lot of interference electromagnetic waves are generated around, and these high-frequency electromagnetic waves have certain interference to nearby instruments and instruments. Therefore, the instruments and electronic systems in the cabinet should use metal casings to shield the interference from the frequency converter to the instruments. All components should be reliably grounded. In addition, the connection between electrical components, instruments and instruments should be shielded control cables, and the shielding layer should be grounded. If the electromagnetic interference is not handled well, it will often make the entire system unable to work, resulting in failure or damage to the control unit.

2) To prevent overvoltage at the input end, the input end of the inverter power supply often has overvoltage protection, but if the high voltage at the input end acts for a long time, the input end of the inverter will be damaged. Therefore, in actual use, it is necessary to verify the input voltage of the inverter, whether it is single-phase or two-phase, and the rated voltage of the inverter. Especially when the power supply is extremely unstable, there must be a voltage stabilizing device, otherwise it will cause serious consequences.

3. Grounding

The correct grounding of the frequency converter is an important means to improve the sensitivity of the control system and suppress noise. The grounding resistance of the grounding terminal E (G) of the frequency converter should be as small as possible. The cross-sectional area of the grounding wire should not be less than 2mm2, and the length should be controlled within 20m. The grounding of the frequency converter must be separated from the grounding point of the power equipment, and the ground cannot be shared. The shielding layer of the signal input line should be connected to E(G), and the other end must not be connected to the ground, otherwise it will cause signal fluctuations and make the system oscillate continuously. The inverter and the control cabinet should be electrically connected. If there is difficulty in actual installation, copper core wires can be used to bridge.

4. Lightning protection

In the frequency converter, there is generally a lightning absorption network, which mainly prevents the instantaneous lightning from invading and damaging the frequency converter. But in actual work, especially when the power line is introduced overhead, the absorption network of the frequency converter alone cannot meet the requirements. In areas where lightning is active, this issue is particularly important. If the power supply is an overhead line, install a special frequency conversion lightning device (option) at the incoming line, or pre-embed a steel pipe 20m away from the frequency converter according to the specifications. Do special grounding protection. If the power supply is introduced by cables, the lightning protection system in the control room should be done well to prevent lightning from entering and damaging the equipment.

Inverter technology is widely used in various industries, from manufacturing to HVAC systems. However, like any other electrical equipment, inverters need to be handled with caution to ensure their safe and efficient operation. This article discusses the precautions that should be taken when using inverters, including considerations for the physical and electrical environment, grounding, and lightning protection. By following these guidelines, users can avoid potential hazards and extend the lifespan of their inverters.

Precautions for Inverter Use

1. Physical environment

1) Working temperature. The inside of the inverter is a high-power electronic component, which is easily affected by the working temperature. The product generally requires 0~55, but in order to ensure safe and reliable operation, it should be considered to leave room for use, and it is best to control it below 40. In the control box, the inverter should generally be installed on the upper part of the box, and strictly abide by the installation requirements in the product manual. It is absolutely not allowed to install heating elements or components that are prone to heat close to the bottom of the inverter.

2) Ambient temperature. When the temperature is too high and the temperature changes greatly, condensation is prone to occur inside the inverter, and its insulation performance will be greatly reduced, and even short-circuit accidents may occur. If necessary, a desiccant and a heater must be added to the box.

3) Corrosive gas. If the concentration of corrosive gas is high in the use environment, it will not only corrode the lead wires of components, printed circuit boards, etc., but also accelerate the aging of plastic devices and reduce the insulation performance. In this case, the control box should be made into a closed structure. , and ventilate.

4) Vibration and shock. When the control cabinet equipped with the frequency converter is subjected to mechanical vibration and shock, it will cause poor electrical contact. At this time, in addition to improving the mechanical strength of the control cabinet and keeping it away from vibration sources and shock sources, anti-seismic rubber pads should be used to fix vibration-generating components such as the external and internal electromagnetic switches of the control cabinet. After the equipment has been in operation for a period of time, it should be inspected and maintained.

2. Electrical environment

1) Prevent electromagnetic wave interference. Due to the rectification and frequency conversion during the operation of the frequency converter, a lot of interference electromagnetic waves are generated around, and these high-frequency electromagnetic waves have certain interference to nearby instruments and instruments. Therefore, the instruments and electronic systems in the cabinet should use metal casings to shield the interference from the frequency converter to the instruments. All components should be reliably grounded. In addition, the connection between electrical components, instruments and instruments should be shielded control cables, and the shielding layer should be grounded. If the electromagnetic interference is not handled well, it will often make the entire system unable to work, resulting in failure or damage to the control unit.

2) To prevent overvoltage at the input end, the input end of the inverter power supply often has overvoltage protection, but if the high voltage at the input end acts for a long time, the input end of the inverter will be damaged. Therefore, in actual use, it is necessary to verify the input voltage of the inverter, whether it is single-phase or two-phase, and the rated voltage of the inverter. Especially when the power supply is extremely unstable, there must be a voltage stabilizing device, otherwise it will cause serious consequences.

3. Grounding

The correct grounding of the frequency converter is an important means to improve the sensitivity of the control system and suppress noise. The grounding resistance of the grounding terminal E (G) of the frequency converter should be as small as possible. The cross-sectional area of the grounding wire should not be less than 2mm2, and the length should be controlled within 20m. The grounding of the frequency converter must be separated from the grounding point of the power equipment, and the ground cannot be shared. The shielding layer of the signal input line should be connected to E(G), and the other end must not be connected to the ground, otherwise it will cause signal fluctuations and make the system oscillate continuously. The inverter and the control cabinet should be electrically connected. If there is difficulty in actual installation, copper core wires can be used to bridge.

4. Lightning protection

In the frequency converter, there is generally a lightning absorption network, which mainly prevents the instantaneous lightning from invading and damaging the frequency converter. But in actual work, especially when the power line is introduced overhead, the absorption network of the frequency converter alone cannot meet the requirements. In areas where lightning is active, this issue is particularly important. If the power supply is an overhead line, install a special frequency conversion lightning device (option) at the incoming line, or pre-embed a steel pipe 20m away from the frequency converter according to the specifications. Do special grounding protection. If the power supply is introduced by cables, the lightning protection system in the control room should be done well to prevent lightning from entering and damaging the equipment.

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