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匿名使用者
匿名使用者 發問時間: 科學其他:科學 · 1 0 年前

關於額定功率 電子學 10點

A certain type of power resistor comes in the following rating: 3W 5W 8W 12W 20W. Your particular application requires a resistor that can handle approximately 8W. Which rating would you use for a minimum safety margin of 20% above the rated value? Why?

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  • 1 0 年前
    最佳解答

    A certain type of power resistor comes in the following rating: 3W 5W 8W 12W 20W. Your particular application requires a resistor that can handle approximately 8W. Which rating would you use for a minimum safety margin of 20% above the rated value? Why?

    20% above the rated value is not enough for long constant current flow.

    Resistor heats up while current flow at least 50% average power comsumption for more secure.

    Rated value is designed with consideration of heatsink not to reach or over 85 degress. good luck !

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