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Wiring 2 relays to 1 switch?

Discussion in 'Lighting' started by spartanhockey6, Jan 22, 2014.

  1. Jan 22, 2014 at 11:27 AM
    #1
    spartanhockey6

    spartanhockey6 [OP] Well-Known Member

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    Trevor
    San Clemente, CA
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    KING 2.5" Coilovers, OME nitrochargers in the rear with Dakar leaf pack, All Pro Apex front bumper.
    Hey guys, I have a quick question about my current wiring setup for my 4 55w hella 500's.

    Right now i have 2 lights> 1 relay>1 switch and then the other 2 lights> 1 relay> 1 switch.

    I currently have the two switches unsecured in the coin/ashtray under the factory switches/blanks. (really annoying)

    What I would like is to use one of the factory blank spots for a switch to power on/off all 4 lights instead of finding a place to mount two seperate switches.

    I've tried doing some research but am not 100% confident in my electrical knowledge lol. Would it be as simple as taking the power wire from relay (A) to the switch (A) and splicing it into the power wire from relay (B) to switch (B)? and then just connecting relay (B) to the new switch?

    Any help is much appreciated. Thanks!
     
  2. Jan 22, 2014 at 12:09 PM
    #2
    Supermoto

    Supermoto Well-Known Member

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    Absolutely, that's one of the great things about using relays. You can have 1 switch trip multiple relays
     
  3. Jan 22, 2014 at 12:16 PM
    #3
    llibrm

    llibrm Well-Known Member

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    Bill
    Convection Oven, Az
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    you need to add up your draw of the relays coil and make sure that your new switch will carry the load. If they're small relays this should be a non issue, but when you start adding multiple items, a 5 second check could save you a ton of time and money later.

    If you have only two relays, you "might" be in the neighborhood of an amp. and your switch "should" carry 5
     
  4. Jan 22, 2014 at 12:19 PM
    #4
    koditten

    koditten Well-Known Member

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    When I'm done it will have a custom fabbed winch bumper and hopefully a Softtopper.
    If the relay is rated, why not run all 4 lights off the one relay?

    Tie all the positives on the lights together and do the same with the negatives. Run a single pair of wires to the relay. 1 switch, 1 relay and 4 lights.

    Just need to find out how many watts the relay will carry.
     
  5. Jan 22, 2014 at 4:42 PM
    #5
    spartanhockey6

    spartanhockey6 [OP] Well-Known Member

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    Trevor
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    KING 2.5" Coilovers, OME nitrochargers in the rear with Dakar leaf pack, All Pro Apex front bumper.
    Thanks for the info guys!

    The two relays i have came with the lights from Hella.

    Both relays are 12V/15A and are probably the size of a 1" cube so they're pretty tiny.

    Since i already have the relays mounted under the hood i'll probably just connect the two power wires from the relays to the one switch.

    What kinda switch do you guys think i should get? 20A? I don't believe my relays are that big and pull enough power so a 20A switch should be good to go?

    Thanks again.
     
  6. Jan 22, 2014 at 10:26 PM
    #6
    joes06tacoma

    joes06tacoma Well-Known Member

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    LEER Shell with dome lights operated with 3 way switches, aux backup lights with relay and 3 position switch, modified wiring to compass/temp display and clock to include switch that disables dimming function (poor man's DRL solution), Scan Gauge 2
    Relays require less than one amp of current to activate. I would run whatever switch you have laying around. I don't think you'll find a automotive switch that is rated less than 3 amps.
     
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