1) Ambient temperature. When the temperature is too high or fluctuates greatly, condensation is likely to occur inside the frequency converter , which will greatly reduce its insulation performance and may even cause a short circuit. If necessary, a desiccant and a heater must be added to the enclosure.
2) Operating Temperature. The inverter contains high-power electronic components that are highly susceptible to temperature fluctuations. The product generally requires a temperature range of 0–55℃, but to ensure safe and reliable operation, a margin of safety should be considered, ideally keeping it below 40℃. In the control box, the inverter should generally be installed on the upper part of the box, strictly adhering to the installation requirements in the product manual. It is absolutely forbidden to install heat-generating or easily heated components close to the bottom of the inverter.
3) Corrosive gases. If the concentration of corrosive gases in the operating environment is high, it will not only corrode the leads of components and printed circuit boards, but also accelerate the aging of plastic components and reduce their insulation performance. In this case, the control box should be made into a closed structure and ventilated.
4) Vibration and Shock. Mechanical vibration and shock can cause poor electrical contact when the control cabinet containing the frequency converter is subjected to mechanical vibration and shock. In this case, in addition to increasing the mechanical strength of the control cabinet and keeping it away from vibration and shock sources, anti-vibration rubber pads should be used to secure vibrating components such as electromagnetic switches both inside and outside the control cabinet. The equipment should be inspected and maintained after a period of operation.
Electrical Environment
1) Prevent electromagnetic interference. During operation, frequency converters generate numerous interfering electromagnetic waves due to rectification and frequency conversion. These high-frequency electromagnetic waves can interfere with nearby instruments and meters. Therefore, instruments and electronic systems within the cabinet should be housed in metal casings to shield them from the frequency converter's interference. All components should be reliably grounded. Furthermore, shielded control cables should be used for connections between electrical components, instruments, and meters, and the shielding layer should be grounded. Improper handling of electromagnetic interference can often render the entire system inoperable, leading to control unit malfunction or damage. Please visit: Power Transmission and Distribution Equipment Network for more information.
2) Prevent input overvoltage. Inverter power inputs often have overvoltage protection; however, prolonged exposure to high voltage can damage the inverter's input terminals. Therefore, in practical applications, it is essential to verify the inverter's input voltage, whether it is single-phase or three-phase, and the inverter's rated operating voltage. Especially when the power supply voltage is extremely unstable, a voltage regulator is necessary; otherwise, serious consequences may occur.
Proper grounding of the frequency converter is crucial for improving the sensitivity of the control system and suppressing noise. The lower the grounding resistance of the frequency converter's grounding terminal E(G), the better. The cross-sectional area of the grounding conductor should be no less than 2mm², and its length should be controlled within 20m. The frequency converter's grounding must be separate from the power equipment's grounding point and cannot share a common ground. The shielding layer of the signal input line should be connected to E(G), and its other end must never be connected to ground; otherwise, it will cause signal fluctuations and continuous system oscillation. The frequency converter and control cabinet should be electrically connected. If practical installation is difficult, copper core wires can be used for bridging.
Inverters typically incorporate lightning protection networks to prevent damage from sudden lightning strikes. However, in practice, especially with overhead power lines, the inverter's lightning protection network alone is insufficient. This is particularly critical in lightning-prone areas. If the power supply is overhead, a dedicated surge arrester (optional) should be installed at the input, or a dedicated grounding system should be installed in a steel conduit at least 20 meters away from the inverter, as per regulations. If the power supply is cable-driven, a proper lightning protection system for the control room is essential to prevent lightning strikes from damaging the equipment. Practice shows that this method is generally effective in resolving lightning strike issues.
