How does a solenoid coil work?

A solenoid valve coil uses electromagnetic energy to create the lateral motion that opens or closes a valve. Consisting of a copper coil around a ferrous metal rod, the solenoid moves when a current passes through the coil, generating a magnetic field that pulls the rod, opening or closing the valve. Solenoid coils are available as N/O (normally open) or N/C (normally closed).