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Switch buying confusion. What is the difference between On - Off - On and (On) - Off - On? Answered

I am having some trouble buying switches from mouser. I need a toggle SPDT switch that has an On - On (on a different line) type workings (like seen here under SPDT). The problem is Mouser has so many different options in their "switch function" filter. Which one(s) should I use? What do the Parentheses mean? Does it mean Momentary or Something else? What about the "None" seen in a few options? What's up with "MOM"? Here is a link to the page I'm talking about.

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framistanBest Answer (author)2013-04-30

Also, be carefull to get the amperes rating you need. A "mini" toggle is pretty small.... and a SUB MINI is really small. Not good for much amperes, but ok for toggling a dataline or similar. ON-ON is probably what you want. If you need it to have an OFF position where NEITHER side is energized, then get the ON-OFF-ON because it has the center off position. If you need the toggle handle to always return to the OFF position when you let go of it, then get the (ON)-OFF-(ON) kind.

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GenAap (author)framistan2013-05-01

Thanks! This helps a lot.

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steveastrouk (author)2013-04-30

Yes, the () means momentary. It is the industry convention.

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AndyGadget (author)steveastrouk2013-04-30

  
+1

Just to clarify - Momentary means it's spring loaded so only makes that contact while you're holding it in that position.

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Josehf Murchison (author)2013-04-29

I take it you want a 2 position toggle switch where one way sends power to one wire and the other way sends power to the other wire.

At mouser in the filter, scroll down to on-on and double check the data sheet.

mouser seams to have only two

642-3645NF
and
642-3635NF

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