The difference between a pressure sensor, a pressure relay, and a pressure switch

The difference between a pressure sensor, a pressure relay, and a pressure switch

The pressure sensor is composed of a pressure-sensitive element and a conversion circuit. Pressure of measured medium transmit to and act on pressure sensitive elements and Produces  the current or voltage output  .Sensors often need to be used with external amplifier circuit to complete the process from pressure detection to control, display and so on.Because the pressure sensor is a primary component, the feedback signal of the pressure sensor must be processed, analyzed, stored and controlled by the measurement and control system to make the industrial automation equipment and Engineering Operation Control more intelligent.

The pressure relay is a signal conversion element of the hydraulic electric switch which uses the liquid pressure to open and close the electric contact.When the system pressure reaches the set pressure of the relay, the electric signal is sent to control the action of the electrical component, to realize the loading or unloading control of the pump, the sequential action of the executive component, and the safety protection of the system, etc. . It is composed of a pressure-displacement conversion component and a Microswitch.According to the structure types of pressure-displacement conversion parts, there are four types: plunger type, spring type, diaphragm type and bellows type. the plunger-type  is divided into a single plunger-type and double plunger-type two. and the single plunger type can also  be divided into plunger, differential plunger and plunger-lever .According to the contact points are divided into single contact and double electric shock.

The pressure switch works according to the set pressure value, it will automatically turn on or off when pressure reaches the set value.Pressure switch and pressure relay are the switch output,only can open or close according to the set pressure and used to carry out a simple bit control.A pressure relay provides more output nodes or node types than a pressure switch.The output of the pressure sensor can be either analog signal or digital signal, which is convenient for post-processing, or can be converted into a standard transmitter signal for long-distance transmission.