Waterproof metal pushbutton switch many varieties of construction:
Can be divided into ordinary button type, mushroom head, self-locking, self-resetting, rotary handle, with light, with a symbol of light and key type, etc.  And not the same combination of methods, usually the choice of modular structure, the button cap, spring reset, bridge contacts and shell, etc., usually made of composite, there is a pair of normally closed contacts and normally open contacts, and some Commodity logarithm of contacts can be added in series with multiple components. There is also a self-restraint button, press it to take the initiative to adhere to the closed position, power off after the open.
Push button switch to start, stop, are rotating, speed and interlocking and other basic control. Usually each button switch has two pairs of contacts. Each pair of contacts consists of a normally open contact and a normally closed contact. When the button is pressed, the two pairs of contacts operate together, the normally closed contacts are opened and the normally open contacts are closed.
In order to indicate the effect of each button, to avoid misuse, the button cap is usually made of different colors to show the difference, the color of red, green, black, yellow, blue, white and so on. For example, red indicates abort button, green indicates start button and so on. The main parameters of the button switch, type, mounting hole dimensions, the number of contacts and the current capacity of the contacts in the product description have specific instructions.
Pushbutton operation method, classification of protection methods, more common types and characteristics of buttons:
Open: Suitable for embedded fixed on the switch board, control panel or console panel. Code-named K.
Maintenance: with maintenance shell, to avoid the internal button parts by mechanical damage or contact with some people charged, code-named H.
Waterproof: with a sealed enclosure to prevent rain intrusion. Code-named S.
Corrosion-resistant: to avoid chemical corrosive gas intrusion. Code-named F.
Explosion-proof: can be used for explosives and dust-rich local without causing explosion, such as coal mines and other occasions. Code-named B.
Knob type: Rotate the handle by hand, there are two positions off and on, usually panel-mounted. Code-named X.
Key-type: Use the key to insert the rotation operation, to avoid misuse or for someone to operate. Code-named Y.
Urgency: There are red mushroom button head protruding from the outside,
Tight for blocking power supply. Code-named J or M.
Self-restraint button: button built with self-restraint using electromagnetic tissue, mainly used in power plants, substations or test equipment, operator interoperability signals and announcements, usually panel operation. Code-named Z.
With light button: The button has a built-in signal lights, in addition to the release of operating instructions, both as a signal indicator, used for control panel, console panel. Code-named D.
Combined: Multiple button combinations. Code-named E.
Interlocking: Multiple contacts interlock with each other. Code-named C.
Classified by Use and Structure:
1, normally open button
2, normally closed button
3, composite button
With round button, square button, rectangle button, high button, mushroom button, mushroom emergency button, pick button, key button