In the magnetic flap level gauge, it is indicated as \"normally open\" and \"self-locking\" – what does this mean?
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In the magnetic flap level gauge, it is indicated as \"normally open\" and \"self-locking\" – what does this mean?
Level gauges equipped with alarm switches can generally be divided into types such as normally open, normally closed, and normally open self-latching. Magnetic rotating column and flap level gauge_Baidu Wenku https://wenku.baidu.com/view/e215f2bea1c7aa00b52acbd9.html
The normally open contacts are connected in parallel with the start button, which is of the normally open type. When the start button is pressed, power flows through the stop button and then to the coil of the contactor; this causes the contactor to engage, and its normally open contacts close. If the start button is released at this point, power still flows through the stop button and to the engaged normally open contacts, keeping the coil powered and the contactor in an engaged state, thus achieving self-protection.