It can be said that we are all familiar with the button switch. The button switch is the most common and frequently used small electrical appliance in our life. We will come into contact with all kinds of button switches in bai’s life and work.In fact, the button switch is a simple structure, the application of a very wide range of main electrical appliances.In electrical automatic control circuits, used to manually emit control signals to control contactors, relays, electromagnetic starters, etc.
Push button switch has a variety of structures, can be divided into ordinary press stud type, mushroom head type, self-locking type, since the reset type, rotary type handle, with light, belt light symbols and key type, etc., have single toggle, double toggle, 3 button compound, a pair of normally closed contacts and normally open contacts, some product can through multiple components in series to increase contact pairs.There is also a self – holding button, after the press can automatically keep the closed position, power off to open.
The button switch can complete the basic control such as start, stop, forward and reverse rotation, change speed and interlock.Typically, each button switch has two pairs of contacts.Each pair of contacts consists of a normally open contact and a normally closed contact.When a button is pressed, two pairs of contacts act simultaneously. Normally closed contacts break and normally open contacts close.
Button switch type classification
Buttons can be classified according to operation mode and protection mode. Common button categories and characteristics:
Open type: suitable for mounting and fixing on switch board.
Button switch (FIG. 2) on the panel of control cabinet or console.Code name K.
Protective type: with a protective shell to prevent the internal button parts from mechanical damage or touching live parts, code name is H.
Waterproof: Sealed enclosure to prevent rainwater intrusion.The code name is S.
Anticorrosive: It can prevent the invasion of corrosive gas in chemical industry.The code name is F.
Explosion-proof type: can be used in places containing explosive gas and dust without causing explosion, such as coal mines and other places.Code name B.
Knob type: rotate the operation contact by hand, there are two positions of on and off, generally for the panel installation type.It’s X.
Key type: use the key insert to rotate for operation, which can prevent misoperation or be operated by specially-assigned person.It’s called Y.
Emergency: Large red mushroom knob protruding from the outside,
Self – holding button: The button is equipped with self – holding electromagnetic mechanism, which is mainly used in power plants, substations or test equipment.The code name is Z.
Light button: the button is equipped with a signal lamp, which is not only used for issuing operation commands, but also serves as a signal indicator. It is mainly used in the panel of control cabinet and console.Code name D.
Modular: combination of multiple buttons.The code name is E.
Interlock: multiple contacts interlock with each other.Code name C.
By use and structure:
1. Normally open button
2. Normally closed button
3. Compound button
Post time: Aug-31-2020