Descriptions:Switch Type: NC(normal closed type), the circuit is closed normally, and, that if a magnet not near it, the circuit open. It consists of a pair of contacts on ferrous metal reed in a hermetically sealed glass envelope. There are two types of reed switches: normally open reed switches and normally closed reed switches. In the presence of a magnetic field, the contacts of a normally-open reed switch will close. A normally-closed reed switch is closed when it is not near a magnet; as a magnet is brought close to it, a normally-closed switch will open. .
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