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Electrical tip needed

Discussion in '80-Series Tech' started by T Y L E R, Nov 27, 2003.

  1. T Y L E R

    T Y L E R

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    Ever notice how hair and wiring seemed woven together ... solder(ing iron) , strands , static , fried , short , 'cetra .... :slap:

    ok , my question is this ...

    • When one intends to 'upgrade vehicle wiring , such as headlights etc , how far does your heavier wiring go towards the load ?

    • Up to the stock pigtails ?
    • Does one upgrade to a heavier pigtailed socket ?
    • What about motors and such ? - Take them apart ??

    --------------------------------[glow=lime,9,900] ???----- ???----- ???----- ???----- ???[/glow]--------------------------------

    T
     
  2. Big_Moose

    Big_Moose

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    T

    As the wire size increases the electrical resistance is reduced. In a direct connection, you would gain nothing, i.e. small wire connected to large wire feeding a device, since the electrical energy is still forced through the small section of wire creating resistance / heat, etc. [same principal as the smaller wire fusible link].

    The new larger gauge wire [smaller numerical number] should start & finish for the entire length of that electrical load. As an example, the headlights should have a larger gauge wire from the power supply to the lamp, so the power flows with little resistance. Since the light switch cannot handle the increase in electrical power, an appropriately rated relay is used.

    Pigtailed socket / connectors should be used according to amperage ratings, i.e. roughly 80% of the total load.

    Depending upon the type of motor [most already have heavy gauge leads for initial startup draw], you could remove & change the leads, but nothing in the LC needs to be changed.

    Generally you upgrade the wiring on the headlamps on the lamp side of the relays while increasing the relay size. Change the battery cables in winch / dual setups. And any accessories you install should include heavy gauge wiring, relays, etc.

    Hope this helps.....and made some sense / tryptophan inhibited!

    Joe
     
  3. T Y L E R

    T Y L E R

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    Yup , That made good sense ... I realized ( naturally :D ) , that lighter ga wiring was useless if it preceeded a heavier upgrade . I wasn't sure though , about the opposite ... ie : 5' of heavy wiring leading up to a load , but joined with 2" of lighter ga wiring . Now I know ... :-\

    I did a smashing job of wiring up the headlight upgrade , though I couldn't find aftermarket pigtails of a heavier grade , so I went with what I could find .. lighter indeed compared to my upgrade harness . I'm going to look around for heavier ga'd light sockets again . Incidentally I swapped over bulbs almost immediately after the upgrade ( hrs ) , and so I noticed a difference there as well ... was enough for me , and I didn't think about it much after that . Now I realize that if I can and do find the right pigtails , I'll gain the full benefit of the harness --- heavy ga from battery to lights , tripped via relays .

    Thanks for confirming what my gut kept trying to tell me .. :beer: :beer:

    T
     
  4. Rich

    Rich

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    In terms of current flow or voltage drop, in a circuit with mixed wire sizes, it makes no difference if the smaller wire is closer to the load or closer to the battery, as the total resistence of the circuit will be the same in either case.
     
  5. Scamper

    Scamper

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    I'll disagree with Warthog a wee bit on one issue: in some cases you actually DO gain something by running larger gauge wiring "most" of the way, with the original or small gauge wiring the rest of the way. Resistance has a length component--that's why when you measure the resistance of your spark plug wires, it's measured in ohms per foot or meter.

    So to make an exagerated example, if you were to run zero gauge wire from battery to the truck's rear, then run a 12g wire from the zero gauge to your equipment, you would be much better off than if you had run 12g from the battery all the way back. Of course, the shorter the 12g the better.

    With 12V systems, the losses are greater than with high voltage systems (e.g,, like 120V wiring) which is: a) why you can have long runs of wiring in your home; b) why the power companys run transmission lines at very high voltages and step it down when it gets to your house; and c) why you need to run large gauge wires for your 12V system.

    If you think of voltage as "pressure" and current as "volume" then it helps some to consider water going through pipes of different diameters (i.e., gauges of wiring) to envision the situation--it takes a lot more pressure to get the same volume of water our of a small-diameter pipe compared to a large diameter pipe. It's not an exact analogy, but it's close...

    But Joe is right that in the best case, the gauge is large as necessary from start to finish. But I think that so long as the pigtails are not seriously long lengths of wire, you don't have a problem and wouldn't see a noticable difference from a change.

    Tom