Often open and normally closed what is the meaning of seeking expert detailed instructions,
Relay in the normal (coil is not energized), the closed contact called the normally closed contact, also known as dynamic contact. Disconnected contacts are often open contacts, also known as dynamic contact.
The relay has eight contacts, generally in the lower part of the two contacts is to start the relay action coil; in the upper part of the relay has six contacts are divided into three groups, each group into the line up and down each have two pay contact, Normally out of the terminal contact with the end of the terminal contact, into the line at the top of the contact is called normally closed contact, the other into the line contact is called normally open contact. But the relay start coil action, the normally closed contact open, normally open contact combination to complete the required action.
When the relay coil is not energized, the contact point is closed, and the contact is open.
After power, often open to normally closed, normally closed will become often open
Normally open: When the coil is not energized, the two contacts are disconnected and the two contacts are closed after power is applied. To the word "H".
Normally closed: When the coil is not energized, the two contacts are closed and the two contacts are disconnected after power is applied. With the word "D" of the word.
A relay is an electrical control device that is an electrical appliance that causes a predetermined step change in the electrical output circuit when the input quantity changes to a specified requirement. It has the interaction between the control system and the controlled system. Usually used in automated control circuits, it is actually a small current to control the operation of a large current "automatic switch". So in the circuit plays an automatic adjustment, security protection, conversion circuit and so on.
In the state of non-energized contact measurement of the pass, power is not long pass, and vice versa
