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Controlling line power with a 6V circuit using a relay.

  1. Nov 7, 2012 #1
    I need a sort of relay which takes only about 6V in the electromagnet, but can handle line current in the connector? It would also be preferable, not necessary, that it's inverted, so when there is power to the coil, the connector is disconnected, and when no power is in the coil, the connector is connected and 120 volts at roughly 12A flows through.

    The only thing I found for this was a SPDT relay, which does not function as I would like.

    Does such a thing exist? If not, what can I do to control a line power switch with a 6V circuit?
  2. jcsd
  3. Nov 7, 2012 #2


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    Many relays have multiple contacts. They are labeled NO (normally open) and NC (normally closed)

    When power is applied the NO contacts will close, the NC contacts will open.

    Try looking for a NC solid state relay.
  4. Nov 7, 2012 #3


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    SPDT should do what you want. Is there a reason you think it would not?
  5. Nov 7, 2012 #4
    To me it seems like the SPDT only has 3 'legs', and can only be integrated into one circuit? I might be mislead by this, how would I use an SPDT with two independant circuits without having them connect with each other?
  6. Nov 8, 2012 #5


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    Thats information you never gave us at the start ;)

    It really helps if you tell us exactly what you are trying to achieve, with circuit diagrams if possible etc.
    That way you will get good direct answers to what you are enquiring about :)

    OK so get a DPDT relay if you have 2 independant circuits you need to control
    and make sure the relay contacts are rated for the voltage and current requirements !!

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