I posted this in rec.autos.tech and either they think their too smart to answer or they don't really know.
Old dodge van, 70's vintage. Alternator wires from back view, two small gauge ones, one is green other red. Two terminals one at 11 oclock one at 2 oclock. Where does the red go and the green? Please don't make me call the dodge dealer for this, haha.
They probably didn't answer because you didn't give enough information. Exactly what year and size alt. Different years use different color wires but in this case, I don't think that it really matters and the field wires should be interchangeable.
He didn't like that answer.
"TBone" wrote in news:46af3d2a$0$32584$ snipped-for-privacy@roadrunner.com:
Sorry, it is a 77 b-100 1/2 ton tradesman van. I think the alternator is the smaller 65? amp one, double grove pulley. Does that help? I guess I really do not understand why they color code the wires if they are interchangeable and seems I remember something about "polarizing" the alternator which would, I'm guessing, imply they are not?
aarcuda69062 wrote in news: snipped-for-privacy@newsclstr02.news.prodigy.com:
Nope, just being careful, don't want to blow something and spend more money if you are wrong. Autozone says the red goes closest to the power wire which is still attached to the alternator. It does not make sense they would colorize the wires if there was not a specific terminal to which each goes. If it turns out you are right you have my apologies.
As I've explained before; the red wire is 12 volt key on, the green wire goes back to the voltage regulator where it is pulled to ground to complete the saturation of the alternator field. Since the two wires perform entirely different functions as noted above, it makes perfect sense that they'd be different colors. The autozoo diagrams do not specify which terminal gets which color wire, their diagrams are simple block diagrams. If it mattered, the terminals wouldn't be the same and they'd be marked. (as GM did, as Ford did, etc.)
Understanding HOW the circuit works negates any notions you may have regarding 'they must be different, there's different colored wires.'
The field circuit is totally isolated, that's why it's called an isolated field circuit. Matters not which terminal gets either color wire. Prior to 1970, you'd have a point (of sorts).
They are color coded because they do different things. One is the 12V feed wire and the other is the ground which is controlled by the regulator. If they were the same color, it would be near impossible to diagnose a wiring problem with the alternator. The alternator in your vehicle has isolated field windings and as such, the wires are interchangeable. If they needed to be connected to a specific terminal, the connectors for each terminal would be different and the two wires would only fit one way.
I can see that. Whether he likes it or not, it is what it is.
I have a factory service manual for '77 D- W- and S-series trucks. The electrical portion would be the same for your B-series. The 18ga red and 18ga light-green wires feed the alternator field. The red is switched to 12V when the ignition switch is in the "run" position. The green is driven to ground by the regulator, using a PWM (Pulse Width Modulated) signal. The more current required from the alternator, the higher the duty cycle.
Because the output of the stator to the rectifiers (inside the unit) is AC, it makes zero difference in the function of the alternator which wire is connected to which terminal (and the service manual makes no distinction).
Bryan
Ok thanks to you and Tbone for the information. I stand corrected in my assumptions. ;-)
"Bryan" wrote in news:iuudnUggrOKnfTLbnZ2dnUVZ snipped-for-privacy@giganews.com:
'isolated' had nothing to do with it, ignoramus
POLARITY is what matters
glad to see you're still around spouting off your stupidity, and that it's still very easy to bitch slap your ignorant ass into next week
LOL, once again, you show your brilliant intellect and that astonishing single digit IQ.
Really, please explain the polarity on an AC device. Now, you do know what AC means, right?!?!?!?!?!
LOL, I do find it funny to watch the stupid and the ignorant pat themselves on the back for the great job that they believe that they have done when in reality, ail they have done is screw the pooch and the rest of us either laugh or just feel sorry for them or in this case, you.
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