Check valve CV12-20 of large flow hydraulic system

Differences among pressure sensors, relays and switches

1. We all often hear about pressure sensor, pressure relay and pressure switch. Are they connected? What's the difference? The following is a detailed introduction of the three. The pressure sensor is composed of a pressure-sensitive element and a conversion circuit, which generates a slightly changed current or voltage output on the pressure-sensitive element by using the pressure of the measured medium. Sensors often need to be used in conjunction with external amplifier circuits to complete the process from pressure detection to control and display. Because the pressure sensor is a primary component, the signal fed back by the pressure sensor needs to be processed, analyzed, stored and controlled by the measurement and control system, which makes the industrial automation equipment and engineering operation control more intelligent.

2. The pressure relay is a signal conversion element of electro-hydraulic switch that uses liquid pressure to open and close electrical contacts. It is used to send out electrical signals to control the actions of electrical components when the system pressure reaches the set pressure of the relay, so as to realize the loading or unloading control of the pump, the sequential actions of the actuators, the safety protection and interlock of the system, etc. It consists of two parts: a pressure-displacement conversion part and a microswitch. According to the structural types of pressure-displacement conversion components, there are four types: plunger type, spring type, diaphragm type and bellows type. Among them, the plunger structure is divided into single plunger type and double plunger type. The single plunger type can be divided into three types: plunger, differential plunger and plunger-lever. According to the contact, there are single contact and double electric shock.

3. The pressure switch is a functional switch that automatically turns on or off when it reaches the set value according to the set pressure.

4. Pressure switches and pressure relays can only be turned on or off under your given pressure, which is used for simple position control. They are all switch outputs! Pressure relay can provide more output nodes or node types than pressure switch. The output of pressure sensor can be analog signal or digital signal, which is convenient for post-processing, and can also be changed into standard transmitter signal for remote transmission.