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Discussion Starter · #1 ·
I'm trying to build my first mod. I want to build a control panel to switch lights and other things up to. I'm learning about electronics to do this but I had a few questions that I know some of you would know. I believe (like I said I'm learning) the battery is DC current, witch the electrons should run from negative to positive. I haven't traced the wire yet, but I thought the negative went to the engine block or frame? Also if I understand correctly, the alternator changes this current to AC? Can anyone explain the wiring in better detail for beginner understanding of current? Does anyone know the amperage the battery puts out and the amp the alternator puts out?

I'll post pictures with schematics when I'm done.

Thanks, Jeff

'83 CJ7 258 i6 31x10.5 3in. lift? /wwwthreads_images/icons/cool.gif
 

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I'll try to help you out Jeff. Everything in a jeep, and most vehicles, is DC, even the output of the alternator. The current the alt puts out depends on the rpm it's turning at, most stock alt' put out 50-80 amps. I think my stock YJ puts out 60ish. You battery only puts out current when you start the engine (cold cranking amps) and can range from 400 cca's to 900 cca's. You can actually crank up your engine and take the battery out and it will run fine if the alternator is operational.

As far as the negative goes, yes, everything electrical is grounded to the chassis. To make a light bulb light up, all you have to do is run one wire to the terminal (through a switch if you want to be able to turn it on and off) and the other wire to a chassis bolt.
Hope that helps, keep at it

/wwwthreads_images/icons/cool.gif Big Ed
'88 YJ, 4" susp,3" body,33's,283 Chevy V8,TH350,4.11's,D30,D35c
 

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If I remember my schooling correctly, electrons do flow from negative to positive, but the convention is to show electricity flowing from positive to negative. The important thing is, it all works out the same, so forget about the electrons and always think of electricity flowing from positive to negative.

Alternators convert the energy required to turn the shaft of the alternator into DC current. This is accomplished by moving one magnetic field through another, which causes an electric current to flow.

Amperage output of alternators and batteries varies, depending how they are constructed.

Hope I haven't made it more confusing,

jerry
 
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Discussion Starter · #4 ·
the alt. doesn't convert to ac, it uses induction to create a current that is used to charge yor battery up after starting and to run your accesories. but,you seem to be getting in deeper than you need to be. the main things you need to know is that all circuits have to be complete in order to work(you need to start at the pos. term of your battery and end at the neg. but since your neg. is tied to your frame you can end the circuit there.) The next thing you need to know is how many lights and what wattage you are installing. the lights are measured in watts. to find the current they'll pull(amps)divide the watts by volts(12)(300 watt lights draw 25 amps). If you want your switches to last you should put dc relays between the switches and the lights. run from a fuse in your fuse box to your switch and out to the coil side of the relay and your wire from your light will connect to one side of the n.o.(normally open) contacts and a fused lead from the side of your battery will connect to the other. The other lead of your light will connect to the frame. Lastly dont forget to size your wire correctly you can find pocket ref. books at elect. supply stores that will tell you what size you need based on the length of the run and the current that will be running through it. if you need some more info feel free to e-mail me at [email protected]

'90 YJ 4" pro-comp susp. TFI upgrade. 258 "not all of them were bought up by yuppies."
 
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Discussion Starter · #5 ·
Thanks for the help guys. I'll post what I come up with.

'83 CJ7 258 i6 31x10.5 3in. lift? /wwwthreads_images/icons/cool.gif
 

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/wwwthreads_images/icons/smile.gif Dear J-head. My moonguy-in-chief/wwwthreads_images/icons/wink.gif of wiring claims that the ONLY way to really do this right is to use relays for everything. He says that if you had even ONE hair on your.....well, you get the idea......that you would get down to Radio Smack and buy a bunch relays, part number 27500226 and go to JCWhitney and buy fuse panel 46377-14 That way, says, moonguy/wwwthreads_images/icons/wink.gif you can run one HUGE wire to the Cole-Hersee fuse panel(yes....it's the same as used in semi trucks) and you have 14 fuses to go anywhere that you want. THEN, you use a tiny toggle switch to "pick" the relay, and the relay puts the major current to the appliance, whatever it may be. My moonguy/wwwthreads_images/icons/wink.gif says that this is the RIGHT way to do this and if you don't do it his way, well......try to imagine a whole LIFE without beer./wwwthreads_images/icons/crazy.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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Discussion Starter · #7 ·
dave is right on with the wiring, and it is easy to do.

now an alternator is just that, it produces alternating current (ac), and via the wonder of diodes you get half wave ac (contrary to popular belief, alternators do not produce true dc).

dan
Good things come to those who do research!!
 

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Bright group here today!
This is usually where most people screw up.
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I really hate having to include a disclaimer, but it's come to the point where I have to...
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Before the 'Nit Pickers' start in, this is a simple explanation, and I an NOT referring to any specific kind or type of generator...
It doesn't have anything to do with make, year model, or anything to do with what someone once told anyone...
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That is true, alternating generators, or alternators as they are commonly called, do NOT produce true Direct Current (DC).
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The produce Alternating Current,
The Alternating Generator passes a strong Magnetic Field through several coils of wire conductor.
(That coiled wire is called the STATOR, and gets it name because it stays Stationary)

That magnetic field causes a reaction in the conductor wire called INDUCTANCE.
The magnetic field INDUCES an electrical CURRENT in the coils of wire.
(Current is any movement of electrical energy)

The Current induced by the magnetic field changes Polarity depending on if the North Pole Field of the Magnet is Inducing the current, Or the South Pole Field is Inducing the Current.

As the North Pole and South Poles of the magnet spin around in the Stator (coils of wire),
Both Positive and Negative POLARITY are created in the same wires.

The changing Polarity of the Stators' current is called, Alternating Current.
Alternating Current (AC) switches polarity several times a second.
Any given conductor in an AC circuit will alternate between Positive and Negative several times a second.
That's why it's called 'Alternating Current'.
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The Alternating Current produced by the Alternator is 'Rectified' by two sets of diodes.

A diode is an electrical check valve that lets current flow one way only, and can be used to pass only the positive or only the negative sides of the alternating current.

By using Diodes, all of the Positive pulses can be separated from the Negative pulses.

Rectified meaning the Positive pulses are separated and collected together.
The Negative pulses are separated and collected also.
This gives you two separate and distinct polarities, Positive and Negative, but they are still a series of very fast Pulses...
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Those Pulses are passed to the vehicle battery.
The battery absorbs the pulses, smooths them out, and combines them with energy already stored in the battery.

This nice, even, homogenized voltage is passed from the battery as true Direct Current to your accessories and appliances.
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Look at the electrical flow like water flow.

The Positive source, in your case, the battery, is the high ground.
To make it move, you need a tube. (Wire.)
The Larger the tube, the more flow or volume. (Larger wire.)
To turn a water wheel or some other accessory, you need a LOT of volume. (Volume Is Amperage)
To squirt a long way, you need pressure. (Pressure Is Voltage)
To make the flow stop, you need a valve. (Switch)
To keep the flow moving, you need drop. (Going To Ground)
The end of the flow would be the low ground. (Ground)
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Most people either really get it, or they don't...
It's like Anchovies, either you love them or you hate them...
There is no 'In-Between' usually...
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Hope this helps verify what's already been said,
Aaron.



I haven't committed a crime. What I did was fail to comply with the law...
 

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/wwwthreads_images/icons/smile.gif What is interesting about the rectifier method of "making" direct current is that it is so widely used. In order to make big motors...like the ones that drive big building exhaust fans for example.....go whatever speed the operator wants, they take normal alternating current that the building gets from the utility company.....then the rectifier sorts it out, putting all the pluses in one pile and all the minuses in another pile....THEN another gizmo takes the pluses and minuses ON DEMAND out of the two piles and makes AC current all over again, but it can make the plus pulse last LONGER and the minus pulse last LONGER IF IT WANTS TO, to make the motor take longer to go pole to pole, and cause a slower speed. The operator just dials what he wants, OR the computer reads the air temp and does it automatically. This is called PULSE WAVE MODULATION, and is the best thing since sliced bread. Previously, you had to have an MG (Motor-Generator) set making true DC and have a huge variable resister to get different speeds. Needless to say this has revolutionized heating, ventilating, and air conditioning./wwwthreads_images/icons/smile.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 

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hey there team rush.. you hit it square and hard.. i teach avionics to young marines.. and sometimes older ones.. but that is the basic way i teach them about electronics.. way to go.. like a job? doesnt pay much.. but the hours are good..
KISS!!!!!

survival is instinct, but living takes guts
 

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I had to print this one out to show my wife why I spend so much time reading what's said on this BBS. I think we should start our own company or maybe even our own country!

Loose nut behind the wheel
Another right-wing conservative.....
Born and raised in Jeep-Town
 

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The generator didn't actually make DC, it made AC and then rectified it at the commutator. It's just not
possible to pass a coil through a field and get DC or vice versa.


 

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/wwwthreads_images/icons/tongue.gif You mean the whatzis did the dumoflogie and then froobled the framis? Is that how it did it?/wwwthreads_images/icons/crazy.gifThose dratted Electrical Engineers! How can we lie successfully if they keep calling us on every little detail!/wwwthreads_images/icons/crazy.gif All this time I've been telling my moonguys/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif that an MG set "makes" DC when it actually is making AC and sending it to the end bell and through the bars on the commutator and through the brushes and back off the other side to the output leads and over to the J-box and into the DC system. THAT'S what I should have told them, but when they are half-crocked on beer so much of the time it becomes necessary to skip a few of the salient details in the intrest of simplicity./wwwthreads_images/icons/smile.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 

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Please correct me if I'm wrong, but I thought the voltage regulator converted the rectified AC from the alternator to DC? So if I have an internal voltage regulator in my alternator, isn't the alternator output DC?

jerry
 

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/wwwthreads_images/icons/crazy.gifEr.....ah....Jerry, rectified AC "IS" DC. The rectifier in the alternator sorts the minuses and the pluses into two separate piles. Only DC comes out./wwwthreads_images/icons/crazy.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 
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Discussion Starter · #16 ·
the regulator only controls the output voltage. this is done by controlling the input voltage.

dan
Good things come to those who do research!!
 

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A Rectifier turns AC PULSES into DC PULSES.
You need a really good capacitor setup or a Nice BATTERY to make it True DC.

All the voltage regulator does is 'Sense' if the system voltage is above or below the cutoff point, and add or subtract current to the electromagnetic field. (The ROTOR)
If the system voltage is low, or under about 13.5 volts, the voltage regulator is a switch, and turns on full current to the ROTOR.
The Rotor is a large rotating electromagnet in the center of the alternating generator.

When the system voltage drops, the VOLTAGE REGULATOR switches on the ROTOR.
The ROTOR produces a larger and stronger MAGNETIC FIELD.
That larger and stronger MAGNETIC FIELD INDUCES more CURRENT in the STATOR.
The higher AC CURRENT makes it's way to the RECTIFIER.
The more AC PULSES in to the RECTIFIER, the more DC PULSES make it out of the RECTIFIER and to the BATTERY.

When the system DC voltage comes back up, the VOLTAGE REGULATOR switches the CURRENT to the ROTOR off, and the alternator effectively stops charging, so it doesn't over charge the system.

The DIODES not only let the AC voltage through one way, but keep the battery voltage from leaking out through the alternator when it's not charging...
(If everything is working correctly...)
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This is much more compact that most designs in the past, but it is by no means a simple procedure.

Inductance is the basic principal that all electrical systems except chemical batteries work from in one way or another.

Inductance is used in the starter motor of you Jeep to get it started, It's used in the distributor pickup coil to trigger the ignition cycle, it's used in the ignition coil to produce the spark energy, and it's used in every electrical solenoid and relay on the vehicle.
Induction is used to generate electricity to replenish the storage battery that started the vehicle.
It is the single most important discovery man has ever made in electricity, and we use it a thousand ways daily, from the generators that make electricity, to the transformers that deliver electricity to your home, to the half a thousand induction devices that make your computer you are reading this on possible...

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To the guy that said all inductance created current is always AC...
Not true.
If you could run a magnet over a length of wire in a straight line, the result would be polarized voltage (DC).

That's not practical to run several hundred feet of wire past a stationary magnet. The pole doesn't change, so the polarity doesn't change.
It's much easier to coil the wire and spin the magnet inside the coil, and that produces AC voltage, because the poles are changing position in relationship to the wire.

That was one of my science experiments in the fifth grade.
I got a 'CHIHUAHUA Plus' on it.
Might have been higher if I hadn't been in direct contradiction of the teachings of the science teacher grading the experiments...
I hear he was a telemarketer for a while. He sells used cars now.
Too bad, he was a fair teacher and a likable guy. (He sucks as a car salesman...)

See ya all.
Time for my pain medication now...
Aaron.

I haven't committed a crime. What I did was fail to comply with the law...
 
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