SPST ..... Single Pole, Single Throw SPDT ..... Single Pole, Double Throw
What does "pole" and "throw" mean? I know just what north and south pole is.
And also telephone pole.
Picture a switch with three connections, labeled 1, 2, and 3. At any time, electrical contact is made either between 2 and 1, or between 2 and 3, depending upon the direction of the switch handle. This would be an SPDT switch...One "pole"...one movable contact, and two "throws"...two positions in which that contact can reside.
Like this:
/---\ /---\ o o o o o o 1 2 3 1 2 3
Get it?
-Dave
-- Dave McGuire "I've watched Harley people throw up Cape Coral, FL on the ceiling." -Krissi
