>To add a little more confusion--
Actually, this is a least consistent...
>A valve having one common port that diverts flow to either of two outlet ports is also called a 3-way (valve).
Are there 4-way valves?
Anyway, a one-way valve lets fluid flow in one direction. A one-way switch isn't really possible with 60 Hz AC current.
A regular valve (two-way) technically lets fluid flow in either direction. A two-way switch lets electric current flow in either direction.
A three-way valve or switch allows flow in any two of three possible directions at a time.
A four-way switch allows flow in any four of eight possible directions at a time.
I definitely like the terms 2-wire, 3-wire, and 4-wire better.
