Types and detection methods of switching devices
The switch is the component that completes the electrical connection and disconnection through a certain action,which is generally connected in series to realize the transmission and control of signal and electric energy.The connector completes the electrical connection between two circuit boards or two parts of the circuit,so as to realize the transmission and control of the signal and the electric energy.The quality and performance of switches and connectors directly affect the reliability of electronic systems and equipment.
Types and detection methods of switching devices
Types of switching devices.The switch can be divided into two categories:manual and automatic;according to the application,it can be divided into power switch,control switch,trip switch and so on;according to the mechanical action,it can be divided into rotary switch,press switch,toggle switch and so on.
The main function of the switching device is to turn on,disconnect and convert the circuit.
The main technical parameters of the switch are rated voltage:the maximum DC voltage or AC voltage effective value that can be withstood under normal working condition.Rated current:the maximum direct current or AC current value that is allowed under normal operating conditions.Contact resistance:a pair of contact points connected to the resistance, the general requirements of < 20m0.Insulation resistance:the resistance between the disconnected conductive parts generally requires 100 Meg ohms.Electrical strength ( pressure ) : the voltage that can be withstood between the disconnected conductive parts, the general switch requires 100V,and the power switch requires 500V.Working life : the number of times used in the normal working condition,the general switch is 5000 ~ 10000 times,the high reliable switch can reach 50000 ~ 500,000 times
Common types of mechanical switches and their detection methods.
Toggle switch and its detection method.The toggle switch is a horizontal sliding transposition switch,which adopts the method of cutting people's occlusal contact and toggling the switch:placing the multimeter in the " RX1 " block,we can measure the condition of the pass between each pin.Dial the multimeter to the " RX 10k " block,and measure the resistance between each pin and the iron shell,which should be infinite.
Straight key switch and its detection method.Direct key switches are often used in electronic devices for band switching,channel conversion,loudness control,and power switches.The outer shell of the direct key switch is a plastic structure,and the contact mode of each group of contacts is a single-pole double-throw type,that is,each group of switches has three contacts,the middle is the knife position,and the two ends of the contact are the toss.The straight key switch is divided into self-reset type and self-locking type.The self-reset switch needs to press the switch handle at work,and when the switch handle is not pressed,the switch can be reset automatically because of the spring action on the switch.A lock spring is arranged on the self-locking switch,and when the switch is pressed,the switch handle is locked by the lock spring to realize self-locking.In order to reset the switch,you must press the switch handle again.This kind of straight key switch also has more than one linkage form.When one of the switches is pressed,the rest of the switches are reset.The two rows of pins of the direct key switch are mutually independent,and are arranged correspondingly,each of which is a group.The detection method is the same as the toggle switch,but group detection is needed.
Detection of conductive rubber switch with multimeter " RX 10 " block should be on state when measuring between any two points of conductive rubber,if the measured resistance is large or infinite,it indicates that the conductive rubber has been invalidated.