Method of charging a frequency converter using a regulated power supply - News - Global IC Trade Starts Here.

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When selecting an adjustable power supply for a frequency converter, it's important to match the input voltage requirements. For single-phase or three-phase 230V AC input, a single-phase 230V AC power supply with 2A output is typically sufficient. This type of power supply can be used to charge both single-phase and three-phase inverters by connecting L+ to L1 and N to either L2 or L3. Since the rectifier circuits are essentially the same, all DC bus capacitors will charge simultaneously. It’s crucial to use the correct voltage level for the inverter’s high-voltage class—such as 400V. The charging process requires very little current because capacitors behave almost like open circuits when initially charged. Therefore, even a low-capacity power supply, such as one rated at 2A, is usually adequate for this purpose. Using a higher capacity power supply isn’t necessary unless specific conditions require it. Always ensure that the power supply is compatible with the system's voltage and current ratings to avoid damage or inefficiency.