20160119 Electrical Question of the Day
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Regarding the rated short-circuit making capacity of low-voltage circuit breakers, one of the following statements is incorrect. ( )A. The rated short-circuit making capacity of a circuit breaker is specified by the relevant product standards or by the manufacturer; it refers to the current value that the circuit breaker can handle under specified voltage, rated frequency, and a certain power factor (or time constant), and is expressed as the maximum expected current peak. B. During a short circuit, the circuit breaker only needs to disconnect the faulty circuit; it does not need to connect it, so there is no such concept as a \"rated short-circuit making capacity\" for circuit breakers. C. The rated short-circuit making capacity of an AC circuit breaker shall be not less than the product of its corresponding rated short-circuit breaking capacity and the coefficient n. D. For DC, assuming that the steady-state short-circuit current is constant, the rated short-circuit making capacity of the circuit breaker should be no less than its rated short-circuit breaking capacity. (B)
It’s great, Z version – give it some encouragement. :):):):):)
B. During a short circuit, the circuit breaker only needs to disconnect the faulty circuit; it does not need to connect it, so there is no such concept as a \"rated short-circuit making capacity\" for circuit breakers.
Regarding the rated short-circuit making capacity of low-voltage circuit breakers, one of the following statements is incorrect. (B) A. The rated short-circuit making capacity of a circuit breaker is specified by the relevant product standards or by the manufacturer; it refers to the current value that the circuit breaker can handle under specified voltage, rated frequency, and a certain power factor (or time constant), and is expressed as the maximum expected current peak. B. During a short circuit, the circuit breaker only needs to disconnect the faulty circuit; it does not need to connect it, so there is no such concept as a \"rated short-circuit making capacity\" for circuit breakers. C. The rated short-circuit making capacity of an AC circuit breaker shall be not less than the product of its corresponding rated short-circuit breaking capacity and the coefficient n. D. For DC, assuming that the steady-state short-circuit current is constant, the rated short-circuit making capacity of the circuit breaker should be no less than its rated short-circuit breaking capacity.
B. During a short circuit, the circuit breaker only needs to disconnect the faulty circuit; it does not need to connect it, so there is no such parameter as \"circuit breaker’s rated short-circuit making capacity\"
Regarding the rated short-circuit making capacity of low-voltage circuit breakers, one of the following statements is incorrect. ( ) A. The rated short-circuit making capacity of a circuit breaker is specified by the relevant product standards or by the manufacturer; it refers to the current value that the circuit breaker can handle under specified voltage, rated frequency, and a certain power factor (or time constant), and is expressed as the maximum expected current peak. B. During a short circuit, the circuit breaker only needs to disconnect the faulty circuit; it does not need to connect it, so there is no such concept as a \"rated short-circuit making capacity\" for circuit breakers. C. The rated short-circuit making capacity of an AC circuit breaker shall be not less than the product of its corresponding rated short-circuit breaking capacity and the coefficient n. D. For DC, assuming that the steady-state short-circuit current is constant, the rated short-circuit making capacity of the circuit breaker should be no less than its rated short-circuit breaking capacity.
B. During a short circuit, the circuit breaker only needs to disconnect the faulty circuit; it does not need to connect it, so there is no such concept as a \"rated short-circuit making capacity\" for circuit breakers.