|Product name||Auto air conditioning refrigeration pressure switch|
|Common parameters||HP:3.14Mpa OFF; MP:1.52Mpa ON; LP:0.196Mpa OFF|
|Applicable medium||R134a, Air conditioning refrigerant|
Generally, pressure switches are installed in automobile air-conditioning refrigeration systems.Pressure protection switches include high pressure pressure switch, low pressure pressure switch, high and low pressure combination switch and three-state pressure switch.At present, it is commonly used as a combination pressure switch. The working principle of the three-state pressure switch is introduced below.
The pressure switch is installed on the high-pressure side of the air-conditioning system.When the refrigerant pressure is ≤0.196MPa, since the elastic force of the diaphragm, the butterfly spring and the upper spring is greater than the pressure of the refrigerant, the high and low pressure contacts are disconnected (OFF), the compressor stops, and low pressure protection is realized.
When the refrigerant pressure reaches 0.2MPa or more, this pressure is higher than the spring pressure of the switch, the spring will bend, the high and low pressure contacts are turned on (ON), and the compressor operates normally.
When the refrigerant pressure reaches 3.14MPa or more, it will be greater than the elastic force of the diaphragm and the disc spring. The disc spring reverses to disconnect the high and low pressure contacts and the compressor stops to achieve high pressure protection.
There is also a commonly used medium pressure switch.When the refrigerant pressure is greater than 1.77MPa, the pressure is greater than the elastic force of the diaphragm, the diaphragm will reverse, and the shaft will be pushed up to connect the speed conversion contact of the condenser fan (or radiator fan), and the fan will run at high speed to achieve pressure protection.When the pressure drops to 1.37MPa, the diaphragm returns to its original shape, the shaft drops, the contact is disconnected, and the condensing fan runs at a low speed.