Because the relay is composed of two parts: the coil and the contact group, the graphical symbol of the relay in the circuit diagram also includes two parts: A long box of relays represents a coil; a set of contact symbols represents a combination of contacts. When the contactless circuit is relatively simple, the contact group is often drawn directly on one side of the coil frame. This drawing is called a centralized representation. Electrical symbols and contact forms: The relay coil is indicated by a long square symbol in the circuit. If the relay has two coils, draw two long square boxes. At the same time, the relay's text symbol "J" is marked in the long box or next to the long box. There are two ways to represent the contacts of a relay: one is to draw them directly on the long square side, which is more intuitive. The other is to draw the respective contacts into their respective control circuits according to the needs of the circuit connection. Usually, the same text symbols are marked on the contacts and coils of the same relay, and the contact groups are numbered. To show the difference. There are three basic forms of relay contacts: 1. When the moving type (normally open) (H type) coil is not energized, the two contacts are disconnected. After energization, the two contacts are closed. It is represented by the pinyin head "H" of the word. 2. When the break type (normally closed) (D type) coil is not energized, the two contacts are closed, and the two contacts are disconnected after power-on. It is represented by the pinyin head "D" of the hyphenation. 3. Conversion type (Z type) This is the contact type. This contact group has three contacts, that is, the middle is a moving contact, and one static contact is provided. When the coil is not energized, the movable contact and one of the static contacts are opened and the other is closed. After the coil is energized, the movable contact moves, so that the original disconnection is closed, and the original closed state is turned off, and the conversion is achieved. purpose. Such a set of contacts is called a changeover contact. It is represented by the pinyin head "z" of the "turn" character. Guangdong Jishengke Industrial Co., Ltd. , https://www.suronart.com
Relay component symbol