Need to pay attention to the use of the inverter - Database & Sql Blog Articles

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1. Ambient temperature significantly affects the lifespan of an inverter. For every 10°C increase in ambient temperature, the life of the inverter can be reduced by half. Therefore, it's crucial to manage the ambient temperature and ensure proper heat dissipation for the inverter. 2. Correct wiring and parameter configuration are essential. Before installing the inverter, always read the manual carefully to understand its operation, precautions, and wiring procedures. After installation, set the parameters accurately based on the intended use. 3. Pay attention to the relationship between motor speed and head pressure. Selecting the right motor and ensuring it operates within its optimal range is vital. If the inverter runs below 5Hz for extended periods, motor overheating becomes a serious issue. 4. V/f control is a constant torque method, while vector control increases motor output torque proportionally to the square of the voltage, which enhances low-speed performance. 5. When operating in power frequency or variable frequency mode, ensure reliable interlocking between the two outputs. The pump should be stopped first, then both power frequency and variable frequency systems should be shut down before operating the contactor. Due to the time required for contactors to open and arc extinction, the sequence and timing of switching must be carefully considered. 6. External control signal failures can occur due to incorrect signal mode, wrong terminal wiring, improper parameter settings, or issues with the external signal itself. 7. Understanding the difference between overcurrent and overload trips is important. Overcurrent protection safeguards the inverter, while overload protection protects the motor. In some cases, the inverter may have a higher capacity than the motor, so it might not trip on overcurrent during motor overload. Instead, the inverter’s built-in thermal protection will activate. It’s essential to correctly set the current take-up ratio—the ratio of the motor’s rated current to the inverter’s rated current. 8. Interference problems can affect system performance. (1) Ensure good grounding. High-power control systems like motors must be reliably grounded via a connection bus. The control system should have an independent ground with resistance under 1 Ω. Connect sensor and I/O interface shields to the control ground. (2) Install EMI filters, common-mode inductors, and high-frequency magnetic rings on input power supplies such as instruments. (3) Adding an EMI filter to the inverter input can suppress conducted interference. Input AC and DC reactors improve power factor and reduce harmonic distortion. If the distance between the motor and inverter exceeds 100 meters, an AC output reactor should be added to prevent leakage current issues caused by wire distribution parameters.