Pressure switches are used to connect or disconnect (open or close) electrical circuits at selected pressures to work with solenoid valves or other devices used in the system.
Pressure switches are used to detect the presence of more pressure Pressure switches use a diaphragm or jumper as a pressure detection element. The motion of this sensor element is used to activate one or more switch contacts for the alarm.
How does a pressure switch work?
The principle of operation of a pressure switch is shown below.
The design includes two separate electrical switches. Each operates with a pressure rod attached to the piston, the position of which is controlled by hydraulic and spring forces. The pressure at which the switches operate is selected by increasing the adjusting screw to increase or decrease the spring force.
It should be noted that in this design, the switches are activated by the springs during unit assembly. So contacts are usually closed and vice versa.
When the pressure reaches the preset pressure, the piston compresses the spring, allowing the pressure bars to move downward, causing the switches to operate and return to their normal position.
By using both switches in connection with the electrical relay, system pressures may be maintained in highly variable high and low ranges.
Where the pressure switch is used:
- Used to limit pressure.
- It is used to work as a safety valve when the pressure is too high
- Pressure switches are used in: boilers, gas compressors, cars, pumps, steam turbines, steam power plants.
The best winners of pressure switches are Danfoss, Vika, UE, Delta.