为了保证用电器的安全使用,设计电路时经常需要用到保护电阻,而保护电阻在电路中接入电路位置不同,保护功能不同,在提高测量精度、可操作方面所起到的效果也不同。下面以常见的限流式电路、分压式电路为例说明保护电阻的选取与运用。一、限流式电路中保护电阻的选取与运用在限流式电路中,闭合开关前,滑动变阻器的阻值应事先调至最大,避免电流过大烧毁电器元件。 In order to ensure the safe use of electrical appliances, the design of the circuit often need to use the protection of the resistance, and the protection of resistance in the circuit access circuit location is different from the protection of different functions in improving the measurement accuracy, the effect of the operation is also different. The following common current limiting circuit, partial pressure circuit as an example to illustrate the selection and application of protection resistance. First, the current limiting circuit protection resistor selection and use In the current limiting circuit, before closing the switch, the resistance of the sliding rheostat should be adjusted to the maximum in advance to avoid excessive current burning electrical components.