Pressure Switches

What is a Pressure Switch?

The pressure switch is a simple pressure control device. When the measured pressure reaches the rated value, the pressure switch can send out an alarm or control signal.

The pressure switch adopts a high-precision, high-stability pressure sensor, and transmission circuit. Then through the dedicated CPU modular signal processing technology, the detection, display, alarm, and control signal output of the medium pressure signal are realized.

Pressure switches can be widely used to measure and control the gauge pressure and absolute pressure of various gases and liquids in the fields of petroleum, chemical industry, metallurgy, electric power, water supply, and other fields.

Featured Pressure Switches

Pressure switch types

Pressure switches can be divided into coil spring tube pressure switches, diaphragm pressure switches, bellows pressure switches, and bellows pressure switches according to the sensing elements.

Pressure switches can be divided into mechanical and electronic smart pressure switches according to their nature.

According to the setting value, the pressure switch can be divided into an adjustable pressure switch and a non-adjustable pressure switch.

Pressure switches can be divided into general pressure switches, small pressure switches, smart pressure switches, explosion-proof pressure switches, marine pressure switches, differential pressure switches, etc. according to applications.

You can learn more about pressure switches by wikipedia.

How does a pressure switch work?

The working principle of the pressure switch:

When the pressure in the system is higher or lower than the rated safety pressure, the disc in the sensor moves instantaneously. Push the switch connector on or off through the connecting guide rod.

When the pressure drops to or rises to the rated recovery value, the disc is instantly reset and the switch automatically resets. Or simply when the measured pressure exceeds the rated value, the free end of the elastic element is displaced. Push the switch after connecting or comparing Element. Change the on-off state of the switch element to achieve the purpose of controlling the measured pressure.

The elastic elements used in the pressure switch include a single-turn spring tube, diaphragm, bellows and bellows. Switching elements include magnetic switches, mercury switches, micro switches, etc.

What is a pressure switch used for?

Pressure switches used in industrial machinery and systems must be robust, reliable, accurate, and have a long service life.

Pressure switches are usually used in paper machines, air compressors or pump sets.

In this type of equipment, we rely on pressure switches to act as safety devices, alarms, or control elements in the system.

Pressure switch air compressor
An ordinary air compressor consists of three main parts: an electric motor, a V-shaped air pump, and an air storage tank.

There is also a pressure switch in the air compressor, which can adjust the start and stop of the motor. By adjusting the pressure in the oil tank, the air compressor can rest.

The air compressor factory can set a certain starting and stopping pressure according to the requirements of different customers during the commissioning process.

For example, when the compressor starts, the air is pumped into the interior. When the pressure reaches the set value, the pressure switch will contact the contact to stop the motor. When the pressure is lower than the set value, the air compressor will start again to keep the pressure in the oil tank within the pressure range.

How do you test a pressure switch?

The calibration method of pressure switch:

  1. Find out the action setting value of the tested instrument according to the specification.
  2. Select an appropriate pressure signal source to pressurize the test meter. A standard pressure gauge with an appropriate range detects the signal pressure. Use a multimeter to measure the on and off states of the contacts.
  3. For the high report switch, slowly increase the pressure from low to high, and observe the multimeter. When the multimeter indicates a sudden change, the evaluation of the standard pressure gauge is the high reported value.
    Then slowly lower the pressure. When the multimeter indicates a sudden change again, the evaluation of the standard pressure gauge is the reset value.
  4. For the under-report switch, the test pressure should be increased above the set value first, and then slowly decreased.
    When the multimeter indicates a sudden change, the evaluation of the standard pressure gauge is a low value.
    Press again slowly, and when the multimeter indicates a sudden change again, the indication value of the standard pressure gauge is the reset value.

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Frequently asked questions

Pressure switches can be divided into three types: explosion-proof, mechanical, and electronic.

Extended reading: Pressure indicator transmitters

The pressure switch is a utility switch that actively turns on or off when the set value is reached according to the set pressure.
Pressure switches and pressure relays can only be opened or turned on under your given pressure to develop easy positional tube bundles. They are all on-off outputs.
Pressure relays generally supply more input nodes or node types than pressure switches.
The output of the pressure sensor can be an imitation signal or a digital signal. It is convenient for the subsequent level to deal with. It can also become a standard transmitter signal for short-range transmission.

As for the difference between pressure transmitter and pressure sensor, many people are not clear. I will tell you today:
The pressure sensor is a sensor that converts pressure into electrical signal output. When the output electrical signal is a standard signal (such as 4-20mA, 0-10mA, etc.), we call it a pressure transmitter. This is the difference between a pressure sensor and a pressure transmitter. So in general, the pressure sensor we often say is actually a pressure transmitter.

You’ll find the pressure switch mounted on a 1/4-in. tube near the pressure tank. It’s what senses when water pressure has dropped to the point where the pressure tank requires more water. The switch then powers up the well pump.

The working principle of the pressure switch: When the pressure in the system is higher or lower than the rated safety pressure, the disc in the sensor moves instantaneously, and the switch connector is turned on or off through the connecting guide rod. When the pressure drops or rises At the rated recovery value, the disc is reset instantly and the switch automatically resets.

Of course, different pressure switches have different ways of resetting. If you need to reset a pressure switch, you’d better contact the manufacturer. Perform reset operation instructions.

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Sino-Inst offers over 50 Pressure Switches for pressure measurement. About 50% of these are liquid pressure swithces, 40% is gas pressure switches.

It is widely used in hydropower, tap water, petroleum, chemical, machinery, hydraulic and other industries to measure, display and control the pressure of fluid media on site.

A wide variety of Pressure Switches options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of Pressure Switch instrumentation, located in China.

Pressure Switches for Sale|Mechanical-Electronic|Gas-Liquid

The pressure switch is a simple pressure control device. When the measured pressure reaches the rated value, the pressure switch can send out an alarm or control signal.

Product SKU: Pressure Switches

Product Brand: Sino-Inst

Product Currency: USD

Product Price: 30

Price Valid Until: 2059-09-30

Product In-Stock: InStock

Editor's Rating:
5