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Help on DIY Relay Panel wiring

Discussion in 'Lighting' started by captain_beefheart14, Apr 25, 2020.

  1. Apr 25, 2020 at 11:50 AM
    #1
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    Help my TW, you're my only hope!

    Ok, I finally finished my relay panel box I've been working on a for a few months, whenever I can spare a few minutes/hours. Got it wired up, and it indeed works, but I have some questions regarding the 87a (I think) white wire from the interior switch. I've attached some photos. Basically, the light bar (only device hooked up to the panel right now) only powers on when I have the 87a White wire connected directly to power, bypassing the terminal strip, which basically defeats the purpose of having the box set up the way it is..

    I've tried having the 87a cable connected to the power out (30) terminal bar, and also the Switch cable (86.)

    To backtrack just a bit, I was previously using a single relay from Cali Raised, which is labeled a bit differently than the ones I purchased on ebay, which makes things a bit confusing. For example, the ground number on the CL relay is 86. The ground on the relay panel is 85.

    I guess my main questions are: what is the white cable, and do I need it?

    IMG_5775.jpg
    White cable (87a possibly) in question
    IMG_5774.jpg
    Relay from CaliRaised prior to swapping to relay panel box
    IMG_5786.jpg
    CR relay panel diagram
    ebay.jpg
    New relays from eBay diagram
    IMG_5781.jpg
    Almost finished with the box, need to work on the side that attaches to the truck and snipping and re-terminating with less slack. A project for another day.
     
    Last edited: Apr 25, 2020
  2. Apr 25, 2020 at 6:52 PM
    #2
    CLVol1255

    CLVol1255 Well-Known Member

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  3. Apr 25, 2020 at 7:00 PM
    #3
    0xDEADBEEF

    0xDEADBEEF Where are we going? Why am I in this handbasket?

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    87a is the normally closed contact. Basically, anytime the relay is not powered, that contact is connected to pin 30.

    Do you have a drawing of what is currently wired to what for both the switch and the relay?

    I would have power from switch going into 86, 85 would be grounded. And then fused power from battery on 87, then your light bar positive on 30. The ground of the light bar would be to ground/frame.

    mini-automotive-relay-wiring-840x.jpg
     
    Last edited: Apr 25, 2020
  4. Apr 25, 2020 at 11:02 PM
    #4
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    I'll have to sort out a drawing. I have 4 gauge power in from battery, through 100 Amp breaker, into Blue Sea Fuse block. 30 (red) should be going from relay to the Fuse Block. I'm (pretty sure) I have ground as 85. I went black cable from relay into negative terminals on Fuse Block when I set it up. 87 (blue) going to power terminal strip, then that (red) cable on to my light. 86 Yellow, is going to the switch (blue cable out from terminal strip upper right.) And then finally a 4 gauge negative cable going back around to the frame.

    What I don't get, is why the white cable in from the switch inside the cab (it's connected to a green cable on the switch harness) HAS to be connected directly to either the fuse block (on the same terminal as the 30 red out from the relay) or to the master positive cable in from the battery/breaker. Why does this cable exist at all? Shouldn't the 86 cable power the switch on/off? The ONLY way the light powers on right now is if this cable in from the switch is attached directly to a power terminal. Only way..

    What I'll probably do tomorrow is pull off the extra relays I have in the box, as I'm not using them any time soon, and sort out exactly what numbers are what. I'm *fairly* certain the diagram in the attached photo (2nd from the bottom in OP) is accurate. I'll compile a diagram and report back here if I don't hear anything else. Thanks.

    current_relay.jpg

    Side of the relays being used currently.
     
  5. Apr 26, 2020 at 8:09 AM
    #5
    caribe makaira

    caribe makaira Well-Known Member

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    OP, look at the base of the original connector TO the original relay. See if there are more than one wire crimped to the base. (wires from the relay base to original switch)
     
  6. Apr 26, 2020 at 6:57 PM
    #6
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    Yes, I did forget to mention that, the "mystery" white cable is in the same pin (87) as switch power.


    Would it be possible to just solder and splice these two before connecting to switch?

    Why would they include two cables here? Seems one to power the switch should suffice.

    IMG_5896.jpg
     
  7. Apr 26, 2020 at 7:17 PM
    #7
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    Here's a quick diagram. I pulled all of the other relays out for simplicity sake:

    relay_panel_simple_diagram.jpg
     
  8. Apr 26, 2020 at 7:56 PM
    #8
    0xDEADBEEF

    0xDEADBEEF Where are we going? Why am I in this handbasket?

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    I had to draw this out, but it looks to me like the white wire should be connected to the cab switch such that when the switch is on, you get +12v on the yellow wire.

    It provides the power that runs the relay coil.
     
  9. Apr 27, 2020 at 12:23 AM
    #9
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    You would think so, but when I have it on the same terminal strip as the yellow, it doesn't work. The light will only work when that cable is attached to the positive portion of the fuse block, or the positive post just past the breaker.
     
  10. Apr 27, 2020 at 2:26 AM
    #10
    caribe makaira

    caribe makaira Well-Known Member

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    upload_2020-4-27_5-26-50.jpg
     
  11. Apr 27, 2020 at 9:17 AM
    #11
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    Do you think I can run that to an under-the-dash fuse? Or is that asking for trouble somehow?
     
  12. Apr 27, 2020 at 3:45 PM
    #12
    caribe makaira

    caribe makaira Well-Known Member

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    Trouble.
    The relay setup you have is meant to "hot" circuit" meaning the vehicle does not have to be ON to function.
    Something like this drawing...

    upload_2020-4-27_18-45-34.jpg
     
  13. Apr 28, 2020 at 7:04 AM
    #13
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    I'm not using that relay anymore though. I'm using a 4-pin now. Yesterday, I snipped the white cable out of the loop entirely, and used an add-a-fuse to a fuse under the dash. It works, but now I'm concerned with what you've stated. The main reason I wanted to move away from the white cable entirely, is I don't have a terminal strip for it. The whole point of having a relay box was to clean up and organize the mess of wires that is going to build in the coming months as I add accessories. If I keep the white hot fused relay wire in the mix, it's just going to be another cable going into the relay box, without organization as it will simply attach to the 30 red terminal spot on the blue sea.

    BUT if I keep it the way I have now, I'm going to soon have about 8-9 add-a-fuses under my dash, which I don't want either. Maybe I should just go with a switch-pro and be done with it, but, that's expensive as shit, and I'm already about $200 into this project..

    Edit: re-reading your post, it looks like your drawing is using a 4-pin as well.
     
    Last edited: Apr 28, 2020
  14. Apr 28, 2020 at 7:10 AM
    #14
    caribe makaira

    caribe makaira Well-Known Member

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    I think you are a bit confused. The WHITE wire is to provide power to the switch, which then sends it back to the relay via the BLUE wire.
     
    0xDEADBEEF likes this.
  15. Apr 28, 2020 at 7:12 AM
    #15
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    I figured that out yesterday I think. But bypassing the relay, can it suffice as is? Meaning: with green wire from switch and red #2 both to add-a-fuses under the dash as opposed to green - white - relay? The red 1 is directed back to the relay.
     
  16. Apr 28, 2020 at 7:14 AM
    #16
    caribe makaira

    caribe makaira Well-Known Member

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  17. Apr 28, 2020 at 7:15 AM
    #17
    caribe makaira

    caribe makaira Well-Known Member

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    You can also use the same feed from the add-a-fuse to ALL switches managing the relays. Not one add-a-fuse per switch like you've stated earlier.
     
  18. Apr 28, 2020 at 7:19 AM
    #18
    captain_beefheart14

    captain_beefheart14 [OP] Well-Known Member

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    Ok, I think I smell what you're stepping in: one "hot" wire (white in previous discussion) from positive terminal on Blue Sea (30 slot) back through firewall, hooked to all switches' relevant wire connections? Well if that's the case, that cleans it up a LOT all around. I've been stressing about having umpteen add-a-fuses under there in the future.
     

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