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What does an "ON-(ON)" switch mean??

Discussion in 'General Electronics Chat' started by Oznog, Sep 8, 2008.

  1. Oznog

    Oznog Active Member

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    Austin, Tx
    I'm looking through Mouser for a SPST latching pushbutton switch. Click on, click off power.

    I see them listed as:
    "()= Momentary"
    OFF-(ON)
    ON-(OFF)
    OFF-ON
    ON-(ON)
    ON-ON
    ON-OFF

    OK the first three I think I get. "OFF-(ON) normally off and momentarily on, right? Then "OFF-ON" would mean latching?

    But by that same line of thinking, "ON-(ON)" would be normally on then momentarily on, which sounds like nonsense, as does "ON-ON". "ON-OFF" would be the same as "OFF-ON" too, the 2 latching states appear identical for a button.

    Am I interpreting this correctly at all? What do "ON-(ON)", "ON-ON", and "ON-OFF" mean??
     
  2. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    This may help.:)

    http://www.kpsec.freeuk.com/components/switch.htm


    EDIT:


    The (ON) brackets mean the toggle is spring loaded and has to be held this position to operate the switch, releasing the switch it will jump back to the previous position.

    So ON-(ON) means that
    if the toggle/lever is in the ON position the switch is latched ON
    if the toggle/lever is HELD in the (ON) position the switch is ON while pressed.

    ON-ON means
    if the toggle/lever is in either of the ON positions the switch is latched ON

    ON-OFF means
    if the toggle/lever is in the ON positions the switch is latched ON
    if the toggle/lever is in the OFF positions the switch is latched OFF
     
    Last edited: Sep 8, 2008
  3. geko

    geko Active Member

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    ON-ON would be have three terminals, common and two switched, when one is on the other is off and vice versa. (single pole, double throw)

    ON-OFF would have two terminals, so it's either on or off (single pole, single throw)

    ON-(ON) the switch doesn't latch in the second position. The (ON) requires someone to hold the switch and it will switch back to ON when they let go. (single pole, double throw, non-latching)
     
  4. dave

    Dave New Member

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  5. rezer

    rezer New Member

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    To me, it's simpler to think of the brackets as a momentary position.
     

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