Calculation of switching power supply input current
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If the switching power supply outputs 24VDC at 10A and the input voltage is 220VAC, what is the input current?
Those who are going upstairs, please do not add “ba” at the end of your sentences! The conditions for this question are not sufficient. The magnitude of the input current is determined by the load on the rear pole, while the magnitude of the output current is determined by the pulse width signal generated by the feedback from the rear pole
What does that mean? What are the complete conditions? Can you give an example? Calculate it
Because the losses of a switching power supply are very small and can be ignored. So when the output is 10A, the input current at the input side is approximately 1.1A. For the convenience of selecting options, 1A or 1.1A is usually chosen; 1A is the standard choice.
1A is likely its maximum allowable value; the actual current is very low, so the value at the input is also uncertain, and it will not exceed 1.1A at most
You should ask what the rated input current is; it’s a little over 1 ampere, as people say. Because switching power supplies and transformers are actually the same thing. The input changes as the output does. If the output is too low, the natural current will decrease. For example, if your power supply is used to power some external solenoids, then once those solenoids operate, some of them will lose power; as a result, their load will decrease, and the current flow will also change.