比率制动差动保护动作特性的确定必须知道最小动作电流、拐点电流和制动系数。
查看答案
比率制动差动保护的动作电流随不平衡电流的增大而增大。
A. 对
B. 错
比率制动差动保护制动特性的斜率越大，灵敏度越高。
A. 对
B. 错
Listen to the conversation between Tom and Yi Fei. Then choose the best answer to each of the questions.听听力，完成下面四道选择题：[音频]1. What does Tom want to know from Yi Fei?
A. If Chinese people like dinner parties.
B. If it is traditional in China to introduce dishes at a party.
C. If Chinese guests would be too embarrassed to cook for others.
D. If Chinese guests would think it impolite to be asked to bring a dish.
Why does Tom want to hold a potluck party?
A. To help him prepare food.
B. To learn more about Chinese food.
C. To cook a dish from his hometown.
D. To let people share their local culture with each other.
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