Jeff Liebermann har bragt dette til os:
On Mon, 28 Oct 2013 12:57:55 -0700, "William Sommerwerck"
wrote:

If anyone is still confused, look at page 2 of this document.
http://www.alliedelec.com/images/pro...S/70155763.pdf

Sigh. Got it. All the desktop publishing computer jocky that created
the data sheet could have done was to put a big "X" in place of the
"NONE", or possibly left the box blank, and there would not be any
confusion. Extra credit if they had added a column with the number of
positions. In any case, it's not very clear as the designation SPDT
could be 2 or 3 positions. Usually, it's marked SPDT center off, from
which the designer is expected to deduce that this is a 3 position
switch. Argh.

I find it fairly obvious.
What is the connections in the center position?
Answer: "It is OFF" - A 3-position switch, center position OFF
Answer: "It is NONE" - A 2-position switch, there is NO center
position

An X would be less obvious.
Answer: "It is X" - I don't know / Crossed over / ????

At least you will only make this mistake once ;-)

Not to insult you, but are you self-taught, or have you formal
education in electronics, or some sort of apprenticeship? You should
have learned the meaning of switch-nomenclature there.

Leif

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