normally closed

基本解释

Proximity limit switch, directly actuated, spring returned, normally closed. Right-click for closed or held open.
直接启动、弹簧复位、正常闭合的邻近限制开关。右击接通或保持断开。
When no channels are selected, the first channel of each bank, which is normally-closed, is connected to an output port.
当没有通道被选中时，每组开关的第一个通道（常闭）被连接到一个输出端口。
This paper introduced the setting of anti-car-running device in inclined lane orbit track and the application of two normally closed anti-car-running device.
介绍了煤矿斜巷轨道运输中挡车装置的设置和两种常闭式挡车装置的应用。
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For five hours this Sunday, some 10 miles of normally car-crowded Los Angeles streets will be closed to vehicular traffic and turned into a massive block party for cyclists, pedestrians, joggers, even stilt-walkers.
FORBES: LA's 10-Mile-Long Block Party