The Collision of Pressure and Signal: The Working Mystery of Electrical Contact Pressure Gauges！

The electrical contact pressure gauge is an instrument that can automatically send signals or control circuits when the pressure reaches the set value. Its "secret" mainly lies in the ingenious combination of structural design and working principle, as follows:    

    
I. Structure and Principles    
·Measurement section: Similar to ordinary pressure gauges, it senses pressure through a spring tube (or diaphragm, bellows), which causes the pointer to rotate and display the real-time pressure value.    
·Electrical contact device: On the dial, in addition to the indicator pointer, there are two (or more) adjustable "contact pointers" (upper limit, lower limit), and both the pointer and the contact have connections to the computer contacts.    
·Working logic: When the indicator pointer contacts a certain contact pointer due to pressure changes, the contact becomes conductive, triggering the external circuit (such as alarms, start/stop of the pump, etc.): When the pressure is outside the set range, the contact opens and the circuit resets.    
    
II. Key "Secret": Precise Control and Flexible Application    
a.Freedom Set     
    The upper and lower limit connection points have manual adjustment functions and can be set according to actual needs to define the pressure range (for example, "the pump starts when the pressure is lower than 0.2 MPa and stops when it is higher than 0.5 MPa"), which is suitable for different scenarios.
    
b.Coordinated Control System    
    Without the need for manual intervention, the relays and contactors can be directly controlled through the on-off of the contacts to achieve automatic start-stop or alarm of the equipment (such as overpressure alarm for pressure vessels, and maintaining pipeline pressure)
    
c.Dual Function
    It can not only display the real-time pressure like an ordinary pressure gauge, but also act as a control element, simplifying the system design and saving costs.

    
III. Usage Notes    
· Avoid frequent on-off of the contacts (which is prone to wear and tear), and it is necessary to reasonably set the pressure range and reduce the number of operations.    
·Contact capacity is limited: When controlling high-power equipment, a contactor is required to be used in conjunction.    
·Regularly clean the contacts to prevent oxidation that causes poor contact and affects reliability.    
    
    
In short, the "secret" of the electric contact pressure gauge lies in seamlessly integrating pressure measurement with electrical control, achieving automated pressure management through a simple structure, and it is widely used in water supply, chemical engineering, machinery and other fields.