See full version: How to excite a gm one wire alternator
Without a good ground, no alternator will properly charge a battery. Tuff Stuff units have an attached tab that can be used for grounding. If the block, brackets, and alternator have no paint or powdercoating to hinder metal-to-metal contact, you might be able to get away with the bracket making the ground connection between the alternator and engine.
With the chrome, cast PLUS+, and powdercoated units, you might need to clean the threads with a thread chaser or tap before installation, as these coatings could interfere with the threads.
This is not usually an issue, as most enthusiasts prefer using a volt gauge to monitor charging. However, Tuff Stuff alternators like the 7127, 7139, and 7140 series can be wired to turn off a warning light. To wire a warning light using one of these battery chargers, simply remove the black terminal plug on the housing and connect the R terminal to the warning-light wire.
Our One-Wire or OEM compatible unit puts out more amperage than an OEM alternator at low RPM. – Frank Hurst[links]
To figure out what amperes output you should use, simply add up the amperes usage of everything in the vehicle. That includes headlights and tail lights, electric fuel and water pumps, and high-power stereo systems. Once you determine your total vehicle amperage draw, add an additional 10-percent just to be safe, and use that number as the minimum amperes output for your application. [links]
An alternator’s only job is to recharge the battery. As lights and other accessories draw current from the battery, energy is replenished by the alternator. To keep the battery fully charged, the alternator must provide more amperes than the accessory load on the battery. A common myth is that a higher amperes-output alternator can hurt the battery. That is not true. If the voltage regulator is properly functioning, it will safely keep the battery fully charged and ready for use. here
Three-wire Alternator:
This setup uses a battery wire, ignition/warning light wire and voltage sensing wire, Three wires. Voltage sensing is used when you want
the alternator to read voltage at some other point than the battery. Or the battery wiring is such that the battery is a long distance from the alternator.
Two-wire Alternator:
Most standard and all self-exciting regulator alternators will work using the two wire setup.
Two wire means that you use the main battery wire to the back of the alternator and also ignition wire to the
#1 terminal to activate the alternator. With this setup the alternator starts charging as soon as the engine is running here
One-wire Alternator:
Is another name for the Self-Exciting Alternator mentioned above. You only need to connect the battery wire (one-wire).
The alternator turns on the voltage regulator when the engine starts turning the alternator.
What is the difference between a one wire alternator, two wire alternator and three wire alternator?
The CS series alternator with self exciting voltage regulator willgive you faster alternator voltage. This type alternator is commonly used on custom cars & trucks, tractors and other non-standard applications when ease of alternator wiring is a factor. In choosing this type alternator you must consider, do you want to rev your motor slightly to get the alternator to turn on, if not the choose the CS series type alternator. Also when using the self-exciting alternator on tractors or other slow turning motors does the engine have enough RPM's to start the alternator charging. This can be overcome by using a smallerpulley or by adding an ignition wire or momentary push button.
Self-Exciting Alternator makes no need for Alternator Wiring Diagram
The Self-Exciting alternator is an alternator that has a special voltage regulator that doesn't need an ignition wire to activate it.This is usually based on a chevy alternator type and only requires a battery wire connected to the battery terminal. The voltageregulator which controls alternator output contains circuitry that uses the residual magnetism in the alternators rotor fields to determine when to turn the alternator on and off, a standard Delco alternator would not do this without an ignition activation wire.The regulator does this by sensing the RPM the alternator is turning, when it gets to a certain rpm the voltage regulator "turns on". Typically you start the vehicle, rev the motor slightly with the si series and alternator starts charging. With the CS series delco alternator with the self exciting voltage regulator you do not need to rev the engine. here
The General Motors one-wire alternator needs to have only one wire connected to operate. This feature has made this unit popular with car enthusiasts and off-road truck builders. With the proper brackets, this alternator can be used with just about any engine and vehicle combination.
Disconnect the negative cable from the vehicle battery. here
Mount the alternator to the engine. It may be necessary to fabricate brackets if they are not available from a speed shop or junkyard. Be certain the belt lines up straight in the pulleys.
Connect a 10-gauge wire from the output stud on the alternator back to the positive battery terminal. Make both connections with a solderless ring terminal. This connection can be made at the starter relay also, as long as it connects to the same terminal as the positive cable from the battery.
Use a wrench to attach the main battery cable to the starter. This cable goes from the battery to the starter and supplies full battery voltage when the starter is activated. Attach a small wire from the ignition switch to the small terminal on the starter solenoid. This controls the starter, turning it on and off when the ignition key is turned.
Bolt the starter in place with a socket wrench. This completes the wiring process. As long as the negative cable is connected to the engine block, the starter will operate. The starter completes the negative circuit through the starter case when it is bolted in place. No separate negative wire is used from the starter to the battery. here
The process for wiring a starter and an alternator on a car is divided into two parts. The first part deals with the power circuit connections because starters consume and alternators produce great amounts of power. The second part involves the control circuits. Starters are turned on and off, and alternator output is regulated, both by their respective control circuitry. By breaking the wiring process down into two categories, the job is easier to understand, and the results are much more predictable.
Bolt the alternator in place. Just like the starter, the negative circuit is completed through the alternator housing. Make sure that it is bolted securely to the alternator mount. Attach a cable directly from the alternator output post to the positive side of the battery. This allows for full output from the alternator to the battery when heavy electrical demands are placed on the alternator.