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Electronics Do these Relays exist?

Discussion in 'Modding' started by pilau, 1 Sep 2007.

  1. pilau

    pilau What's a Dremel?

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    I was wondering if these two types of relays exist:

    - Relay which recieves current and then connects the poles only for a moment
    - Relay which recieves a momentary current and then connects the poles, and when it recieves another current it disconnects the poles

    Thanks.
     
    pilau, 1 Sep 2007
    #1
  2. bubsterboo

    bubsterboo What's a Dremel?

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    Not that i know of because of the mechanics of a relay. But you could design a really simple circuit with two relays to do that exact thing.
     
    bubsterboo, 1 Sep 2007
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  3. ElThomsono

    ElThomsono Multimodder

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    "Relay which recieves a momentary current and then connects the poles, and when it recieves another current it disconnects the poles"

    Certain latching relays operate like that.
     
    ElThomsono, 1 Sep 2007
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  4. radodrill

    radodrill Resident EI

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    Standard relays are momentary.

    Latching relays are available in 2 flavors:
    -single coil = apply voltage with positive polarity to set and negative polarity to reset
    -dual coil = current across one coil to set and across the other coil to reset.
     
    radodrill, 1 Sep 2007
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  5. pilau

    pilau What's a Dremel?

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    Really? I thought that they hold the poles together as long as the voltage is applied, isn't it like that?
     
    pilau, 1 Sep 2007
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  6. Xen0phobiak

    Xen0phobiak SMEGHEADS!

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    thats exactly what momentary is.
     
    Xen0phobiak, 1 Sep 2007
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  7. cpemma

    cpemma Ecky thump

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    The second type are sold, but will cost you a lot.
    Can also be done cheaper with three more common relays.

    [​IMG]

    Or just a solid-state flipflop.

    The first type I've not seen on sale, a 555 monostable is the cheap way, though I think it could be done with two DPCO relays.
     
    cpemma, 1 Sep 2007
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  8. radodrill

    radodrill Resident EI

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    Just think of mechanical pushbuttons:
    Momentary = Push to make/release to break
    Latching = Push to make/Push to break
     
    radodrill, 1 Sep 2007
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  9. radodrill

    radodrill Resident EI

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    Only ~$3.50 US; but it is a few times more expensive than standard relays.
     
    radodrill, 1 Sep 2007
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  10. pilau

    pilau What's a Dremel?

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    When I said "moment", I meant that once the voltage is applied, it only connects the poles for a brief moment, and then releases them, even if the voltage is still applied. What do you say? Such a thing exists? Or do I have to design my own circuit?
     
    pilau, 1 Sep 2007
    #10
  11. cpemma

    cpemma Ecky thump

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    This ratchet one is around £45 here, HK$560 or AUS$160. :( Can't find a US$ price.
     
    cpemma, 1 Sep 2007
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  12. cpemma

    cpemma Ecky thump

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    The "1-second one-shot" circuit will do what you describe. To get a second pulse you need to first turn the switch off to reset things.
     
    cpemma, 1 Sep 2007
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  13. pilau

    pilau What's a Dremel?

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    The link is not working...
     
    pilau, 1 Sep 2007
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  14. cpemma

    cpemma Ecky thump

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    WFM :confused:
     
    cpemma, 1 Sep 2007
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  15. Xen0phobiak

    Xen0phobiak SMEGHEADS!

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    It says the session has timed out to protect your privacy.
     
    Xen0phobiak, 1 Sep 2007
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  16. radodrill

    radodrill Resident EI

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    link doesn't work; but for that price it must be a high current industrial relay.
     
    radodrill, 2 Sep 2007
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  17. cpemma

    cpemma Ecky thump

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    cpemma, 2 Sep 2007
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  18. radodrill

    radodrill Resident EI

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    radodrill, 2 Sep 2007
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  19. ConKbot of Doom

    ConKbot of Doom Minimodder

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    ConKbot of Doom, 3 Sep 2007
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