Explain the purpose of normally open and normally closed solenoid valve
Normally closed (NC) 3-way valves block the path between the inlet and outlet ports until the coil is energized. The outlet port is connected to the exhaust port when de-energized and this path becomes blocked once the coil is energized, linking the inlet and outlet instead.
Normally open (NO) means that the valve is open and fluid flows from the inlet to the outlet and the exhaust port is blocked when the coil is de-energized. When the coil is energized, the inlet port will close and the flow path from the outlet to the exhaust be opened