Solenoid valve is integral part of Electro. This valve will control the supply of air to inletor valve in load/unload operation of reciprocating. Different types of solenoid are available in market. In Compressor Technology Normally open (N/O) or Normally Close (N/C) type solenoid valve are used to perform loading/unloading action.
Use of each port is as below
Impulse air supply through tube of Dia. not less than 12 mm from the air receiver through control filter connected to inlet port of solenoid valve.
This port is also known as port. This is connected through, at least 6 mm Dia. Copper or Nylon tube to inlet (Suction) valve of the compressor.
This port is for the escape of trapped air in the line. It should always keep open to the atmosphere.
Normal Open (N/O)
This type solenoid valve allows air supply to flow from inlet port to outlet (cylinder ) port, in de-energized or normal condition. When energised, due to change over in pressure contact stops the air supply. This type of solenoid valve are used for load/unload operation of air compressor.
Normal Close(N/C)
This type of solenoid valve does not allow air supply from inlet port to outlet port in de-energized or normal condition. When energized due to change over in contact of pressure switch allows air supply to flow through cylinder port. This type of solenoid valve is used in 5-step control panel for increasing and decreasing the area of clearance pocket during unloading/loading operation of Air Compressor.