Why do some solenoid valves use mesh screens?
The mesh screen is intended for the protection of the internal components of the solenoid valve. The mesh catches small pieces of debris that could impede the spool or poppet movement. However, the screen is not recommended for primary filtration.
What are normally closed valves?
A 2-way, normally closed poppet valve acts as a check valve when de-energised, thus blocking flow from one direction and allowing restricted free flow in the reverse direction. When energised, the poppet lifts and allows free flow from the side to the nose of the cartridge. If the application requires free flow in both directions, the free reverse flow option should be chosen.