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Author Topic: What is a Self Exciting (One-wire) Alternator?  (Read 9761 times)


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What is a Self Exciting (One-wire) Alternator?
« on: November 23, 2009, 04:26:17 PM »
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[h=1]What is a Self-Exciting Alternator?[/h]
Will it Solve Alternator Wiring Problems?

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 voltage regulator 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 type alternator with the self-exciting voltage regulator you do not need to rev the engine. The CS series alternator with self exciting voltage regulator will give 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 smaller pulley or by adding an ignition wire or momentary push button.

[h=3]One-wire Alternator:[/h]
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.

[h=3]Two-wire Alternator:[/h]
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.

[h=3]Three-wire Alternator:[/h]
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.

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What is a Self Exciting (One-wire) Alternator?
« on: November 23, 2009, 04:26:17 PM »