The pressure sensor is composed of a pressure sensitive element and a conversion circuit, using the pressure of the measured medium acting on the pressure sensitive element to produce a slight change in the current or voltage output. Sensors often need to cooperate with external amplifying 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 needs to be processed, analyzed, stored and controlled through the measurement and control system, so that the industrial automation equipment and engineering operation control, more intelligent.
Pressure relay is a signal switching element of hydraulic electric switch which uses liquid pressure to open and close electrical contacts. When the system pressure reaches the set pressure of the relay, the electric signal is sent out to control the action of the electrical components, so as to realize the loading or discharging control of the pump, the sequential action of the executing components, the safety protection and interlocking of the system, etc. It is composed of two parts: pressure - displacement converter and micro switch. According to the structure type of pressure-displacement conversion parts, there are four types: plunger type, spring type, diaphragm type and bellows type. The plunger structure is divided into single plunger type and double plunger type two. The single plunger type can be divided into three types: plunger, differential plunger and plunger - lever. According to the contact points, there are single contact and double electric shock.
The pressure switch is a function switch that automatically switches on or off when it reaches the set value according to the set pressure.
Pressure switch, pressure relay, you can only be given pressure, open or close the switch, used for simple bit control, are switching quantity output! Pressure relays can provide more output nodes or node types than pressure switches. The output of the pressure sensor can be analog signal or digital signal, which is convenient for post-processing and can also be converted into a standard transmitter signal for remote transmission.