Pins 4 and 8 represent the coil legs of the relay, which is the rated voltage labeled on the top of the relay.
Pins 1, 2, and 3 are the first set of contacts, pin 2 is the common **** pin for the first set of contacts, pin 1 is the normally open pin for the first set of contacts; pin 3 is the normally closed pin for the first set of contacts.
Pins 5, 6 and 7 are the second set of contacts, pin 6 is the male **** pin of the second set of contacts, pin 5 is the normally open pin of the second set of contacts, and pin 7 is the normally closed pin of the second set of contacts.
Expanded Information
There are three basic forms of relay contacts:
1, dynamic close type (normally open) (H-type) The coil is not energized when the two contacts are disconnected, and when energized, the two contacts are closed. The word "H" is the phonetic prefix of the word "H".
2, dynamic break type (normally closed) (D type) coil is not energized when the two contacts are closed, energized, the two contacts will be disconnected. The word "D" is the phonetic prefix of the word "break".
3, conversion type (Z type) This is the contact group type. This contact group *** there are three contacts, that is, the center is a dynamic contact, up and down a static contact. Coil is not energized, the dynamic contacts and one of the static contacts disconnected and another closed, the coil is energized, the dynamic contacts will move, so that the original disconnected into closed, the original closed into the disconnected state, to achieve the purpose of conversion.
Such a contact group is called a switching contact, with the "turn" of the word pinyin head "z" said.
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