电动机在运行中为什么会发出噪音？怎样处理？
参考答案：
电动机在运行中发出噪音，可能是保险丝一相熔断或者是电压突然下降，电动机三相电流不平衡，电动机转子与定子磨擦造成的。可以根据这些原因，对电动机和附属设备进行检查，如果是电动机一相保险丝熔断，电动机停止运转后，再开动时便开动不起来，这样可以找出保险丝熔断的原因，换上新的同容量的保险丝之后，再开动电动机。
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| My father enjoys bike riding. Ever since I was little, I've always loved going biking with my dad. 1 , as I became a teenager, other things began to draw my 2 . It was important to do things with friends 3 . I saw my dad every evening at home. Why did I have to 4 my Sundays to all-day bike trips with him, too? If my indifference (冷漠) hurt him, my father kept 5 , but he would always let me know when he was planning a bike trip 6 I wanted to come. It was a Sunday morning, and I was in low 7 .Two of my friends had gone to the movies without inviting me. Just then my father 8 my room. "It's a beautiful day. Want to go for a 9 today, Beck?" "Leave me alone!" I impatiently 10 .Those were the last words I said to him before he left the house that 11 . Several hours later, the police called us, 12 us that Dad had a traffic accident. My father's injuries were serious. It took several days before he could 13 speak. Beside his bed I held his hand gently, 14 of hurting him. "Daddy … I'm sorry …" "It's OK, sweetheart. I'll be OK." "No," I said, "I 15 what I said to you that day. You know, that morning?" "Sweetheart, I don't 16 anything about that day, not before, during or after the accident. I remember kissing you goodnight the night before, though." He 17 a weak smile. I felt regretful for my thoughtless remark, for I 18 wanted him to leave me alone. My teacher once told me that 19 have immeasurable power. They can hurt or they can heal. And we all have the 20 to choose our words. I intend to do that very carefully from now on. | ||||
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