题目

英语翻译
Some contacts are normally open (Abbreviated "n.o." or "no") until closed by operation of the switch,while others are normally closed ("n.c.or "nc") and opened by the switch action,where the abbreviations given are commonly used on electronics diagrams for clarity of operation in assembly,analysis or troubleshooting.The serve to synchronize meaning with possible mistakes in wiring assembly,where wiring part of switch one way and part another (usually opposite) way will pretty much guarantee things won't work as designed.

提问时间：2020-11-03

答案

有些开关的触点,正常情况下是断开的（缩写为：n.o 或no,是normally 和open的缩写）,操作开关将其闭合；而有些触点则是常闭的（缩写为：n.c或nc,是normally 和close的缩写）,操作开关将其断开.以上缩写形式通常在组装,分析或故障维修用的的电路说明图中使用.