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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?
1 個解答
- 釋大懺Lv 71 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 !
