The pressure switch is a simple pressure control device. When the measured pressure reaches the rated value, the pressure switch can send out an alarm or control signal.
The working principle of the pressure switch is: when the measured pressure exceeds the rated value, the free end of the elastic element is displaced, and the switching element is pushed directly or after comparison to change the on-off state of the switching element to achieve the purpose of controlling the measured pressure.
The elastic elements used in the pressure switch include a single coil spring tube, diaphragm, diaphragm, bellows, etc.
Switching elements include magnetic switches, mercury switches, micro switches and so on.
There are two types of pressure switches: normally open and normally closed.
There are two adjustment modes of the pressure switch, two-position type and three-position type.
Accuracy: A value indicating the accuracy of the equipment, including linearity, tolerance, hysteresis, repeatability, etc. At present, the highest accuracy of pressure switch in Nagano can reach ±0.5% F.S. The model is CB33.
Maximum pressure (Max.P): the maximum value of the pressure range.
Full scale (F.S): The difference between the maximum and minimum pressure range.
Disconnection difference (dead zone): refers to the difference between the switch setting action value and the reset value. For example, when the set value is 1MPa and the actual reset value is 0.9MPa, the connection and disconnection difference is 0.1MPa.
Operating temperature: refers to the temperature range within which the internal mechanism and sensitive components of the instrument will not undergo continuous deformation during operation. Generally, the recommended operating temperature range of pressure switches is -5~400C. If the medium temperature is too high, you can consider adding an accessory siphon (filled) to achieve the purpose of cooling.
S.P.D.T (Single Pole Double Throw): Consists of a normally open, a normally closed contact and a common terminal.
D.P.D.T (Double Pole Double Throw): It consists of a symmetrical left and right common terminal and two groups of normally open and normally closed terminals.
Upper limit one contact (normally open): When the pressure rises to the set value, the contact will act and the circuit will be turned on.
Lower limit one contact (normally closed): When the Yali drops to the set value, the contact will act and the circuit will be turned on.
Upper and lower limit two contacts HL: It is a combination of upper limit and lower limit, divided into two types of independent action of two contacts (dual setting, double loop) and simultaneous action of two contacts (single setting, double loop).
Upper limit 2 contact: Combining two upper limit forms, divided into two types of independent action of two contacts (dual setting, double circuit) and simultaneous action of two contacts (single setting, double circuit).
Lower limit 2 contacts: Combining two lower limit forms, divided into two types of independent action of two contacts (dual setting, double circuit) and simultaneous action of two contacts (single setting, double circuit).
Pressure resistance: The maximum pressure that the pressure switch can withstand while maintaining its normal performance. However, when the pressure switch is used in overpressure situations, the sensitive components will undergo continuous deformation, and the pressure setting value will change at this time, and the pressure switch will not be able to perform its normal performance and may even be damaged.