二次回路标号的基本方法是什么
参考答案：(1)用三位或三位以下的数字组成，需要标明回路的相别或某些主要特征时，可在数字标号的前面(或后面)增注文字符号。 (2)按“等电位”的原则标注，即在电气回路中，连于一点上的所有导线(包括接触连接的可折线段)须标以相同的回路标号。 (3)电气设备的触点、线圈、电阻、电容等元件所间隔的线段，即看为不同的线段，一般给予不同的标号；对于在接线图中不经过端子而在屏内直接连接的回路，可不标号。
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| This year 1 the 100th anniversary of the sinking of the Titanic. Like some American 2 in the 2008 financial crisis, the ship was thought to be "too big to 3 ". But the banks failed and the Titanic failed.. .spectacularly! After hitting an iceberg, it plunged to the bottom of the 4 Ocean. In less than three hours, the "unsinkable" ship was just a wreck and over1,500 people were dead. Most of us know the story of the Titanic from watching the James Cameron film. It's now been released in a 3D version and new audiences can see the tragic event 5 and be moved by the love story of the two main characters, Jack and Rose. But Titanic is 6 a love story; it's the story of 7 ordinary people react when faced with 8 circumstances. In 1852, the HMS Birkenhead foundered on rocks near the coast of South Africa. The British ship was carrying soldiers, and also many women and children. There weren't enough 9 for everyone so the order was given, "women and children first." 10 the women and children were being saved, the soldiers stood at attention on deck and, 11 , went down with the ship. They faced their death with bravery and 12 . The 13 , "women and children first," became the standard on all British ships and it's exactly what happened on the Titanic. The ship's crew and many passengers realized that they would not be saved, 14 they did not panic. They helped others or 15 calmly for the icy death they knew was inevitable. In the movie, we see the ship's musicians playing to help 16 the passengers. We see the ship's officers keeping order as the lifeboats are loaded. And we see British gentlemen "keeping their heads" as all about them are losing theirs. No one knows how they will react in the face of a disaster. It all 17 one's character. Remarkably, most people behave well. We have seen this in America's 911, in the 2008 Sichuan 18 and in Japan last year. 19 such as the Titanic will happen, but the character of good people is 20 . | ||||
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