What is a process switch ? What is an electrical contact meter ?

It is also called a travel switch, or a limit switch. The function is the same as that of the button switch, that is, the electrical appliance that sends instructions to the control circuit to turn on or off and signal, and the principle is to use the collision of some moving parts of the production machinery to make it move. The commonly used one in China is the JLXK1-111 type.

Electrical contact type meter (this is on my computer, copied to you, we rarely use this anymore, and now we all use digital display instead.) ）

Product Introduction: 1. Description of use:

The electric contact pressure gauge is suitable for measuring the pressure of various liquids, gases and other media that are non-corrosive, non-dangerous and non-crystalline for copper alloys. The instrument can be used with the corresponding electrical devices to achieve the purpose of dual-position automatic control and signaling (alarm) of the preset maximum or minimum pressure value for the measured pressure system.

The instrument has the function of measurement and control, which can arbitrarily set the upper and lower control pressure value, and the action is stable and reliable, and it is widely used in petroleum, chemical, power station, metallurgical and other industrial enterprises and mechanical and electrical equipment.

Detailed introduction: 1. Description of use:

The electric contact pressure gauge is suitable for measuring the pressure of various liquids, gases and other media that are non-corrosive, non-dangerous and non-crystalline for copper alloys. The instrument can be used with the corresponding electrical devices to achieve the purpose of dual-position automatic control and signaling (alarm) of the preset maximum or minimum pressure value for the measured pressure system.

The instrument has the function of measurement and control, which can arbitrarily set the upper and lower control pressure value, and the action is stable and reliable, and it is widely used in petroleum, chemical, power station, metallurgical and other industrial enterprises and mechanical and electrical equipment.

2. Structural principle:

The instrument is composed of a measuring system, an indication device, a magnetic contact device, a shell, an adjusting device and a junction box.

When the measured pressure acts on the spring tube, its end produces the corresponding elastic deformation - displacement, which is amplified by the transmission mechanism and indicated by the indicator device on the degree plate. At the same time, the pointer drives the moving contact of the electric contact device to contact the contact (upper or lower limit) on the set pointer instantaneously, causing the control system to turn on or off the circuit, so as to achieve the purpose of automatic control and sending alarm.

On the electrical contact signal pin of the electrical contact device, an adjustable permanent magnet is installed, which can increase the contact suction and speed up the contact action, so that the contact contact is reliable, eliminate the arc, and effectively avoid the frequent shutdown of the contact caused by the vibration of the working environment or the fluctuation of medium pressure. Therefore, the instrument has the advantages of reliable action, long service life, and large contact switching power.

Electrical parameters and control forms of contact devices.

Process switches refer to switches used in the field of process control. Mainly pressure or differential pressure switches.

This belongs to the electrical contact type meter you asked later.

Conventional gauges indicate numerical values. The electric contact instrument is an instrument with an electric contact, which is used in the field of control. When the values it controls (such as temperature, pressure, liquid level, etc.) reach the set value, its contacts will act (close or disconnect), thus controlling or protecting the equipment.

1.Overview.

Pressure and differential pressure process switches (pressure, differential pressure controllers) refer to various pressure or vacuum degree over-limit transmission devices made by the strain principle of elastic elements. When the pressure rises or falls, the elastic element is deformed (such as the bellows is elongated or shortened), and the contact is closed or disconnected through the lever and the boom arm to achieve the purpose of two-position control.

2.Technical Specifications.

There are many varieties of pressure controllers, and different manufacturers have different models, but they can be summarized as follows (classified by measurement sensor):

1) Diaphragm sensor: Measure micro and low pressure.

2) Bellows sensor: Measure medium and low pressures.

3) Piston sensor: Measure medium and high pressure.

It's a travel switch.

and electrical contact pressure gauges.

Proximity switch is a position switch that can be operated without mechanical direct contact with moving parts, when the sensing surface of the object proximity switch to the operating distance, the switch can be operated without mechanical contact and any pressure, so as to drive DC electrical appliances or provide control instructions to computer (PLC) devices. Proximity switch is a kind of switch sensor (i.e., no contact switch), which not only has the characteristics of travel switch and micro switch, but also has sensing performance, reliable action, stable performance, fast frequency response, long application life, strong anti-interference ability, etc., and has the characteristics of waterproof, shockproof, corrosion resistance, etc. The products are inductive, capacitive, Hall, AC and DC types.

Proximity switches, also known as contactless proximity switches, are ideal electronic switching sensors. When the metal detector is close to the sensing area of the switch, the switch can be contactless, no pressure, no sparks, quickly issue electrical instructions, accurately reflect the position and stroke of the moving mechanism, even if it is used for general stroke control, its positioning accuracy, operation frequency, service life, convenience of installation and adjustment and adaptability to harsh environments are incomparable with general mechanical travel switches. It is widely used in machine tools, metallurgy, chemical industry, textile and printing industries.

In the automatic control system, it can be used as limit, counting, positioning control and automatic protection link.

Among the various types of switches, there is a component that has the ability to "sense" objects approaching it.

Proximity switches. – Displacement sensors. The sensitive characteristics of the displacement sensor to the approaching object are used to control the switch on or off, which is the proximity switch.

When an object moves towards the proximity switch and approaches a certain distance, the displacement sensor will "sense" and the switch will act. This distance is usually referred to as the "detection distance". However, different proximity switches have different detection distances.

Sometimes the objects to be inspected are moved to the proximity switch one by one at certain intervals, and then leave one by one, and so on and so forth. Different proximity switches have different responsiveness to the detected object. This response characteristic is known as the "response frequency".

Wiring instructions. 1.The three wires of the DC three-wire proximity switch are: brown wire--- positive power supply, blue wire--- negative power supply, black wire--- output signal.

2.AC two-wire switch: The load and proximity switch are connected in series to the AC power supply.

There are two types of proximity switches commonly used: capacitive and inductive.

Capacitive proximity sensors can be applied to any non-gaseous surface, such as cloth, paper, etc. It is measured by the amount of change in air capacitance over a certain distance ahead.

Inductive proximity sensors can only be applied to the surface of metal objects, such as iron, aluminum, etc. It emits an alternating electromagnetic field of a certain frequency and completes the detection by detecting the change of the electromagnetic field of the measured object. Usually it is more sensitive to steel and less sensitive to aluminum, copper, etc.

They are used in the same way, they are both an active component that needs to be plugged into a power source. But they all have a variety of output forms, there are relays, transistors, but also divided into normally open and normally closed, as well as open and leaky, the specific connection depends on the specific model. Generally, there will be a label on its shell, indicating the working voltage, sensing distance, output mode, etc. of the switch, and it can be used accordingly.

Proximity switch Xinling proximity switch Model** Xinling Electric.

Now the voice-activated switch and light-controlled switch are all ah.