3-way solenoid valve Normally Open

What is a 3-way Solenoid Valve ?

3-way solenoid valves operate in a manner analogous to single-pole double-throw (SPDT) electrical switches: with two paths for flow sharing

2-way solenoid valve Normally Closed

What is a 2-way Solenoid Valve ?

2-way solenoid valves operate in a manner analogous to single-pole single-throw (SPST) electrical switches: with only one path for flow.