Funky alternator wiring- '73 Duster
Paul,
The heavy gage black wire is alternator output.
Lets break this up by first covering what the black wire does. Then we'll cover what the other two alternator wires do.
Cars have two power sources: Battery & Alternator.
Power flows from whichever one can supply at the higher voltage.
> Battery can supply power at approximately 12.5 Volts.
> Alternator can supply power at approximately 14 Volts when its running.
The output wire from the battery and the one from the alternator are joined at the main splice. From that junction power is fed to the key switch, fuse box, headlight switch.
In the illustration below the main junction is represented by a solid black dot.
All of the wires joined at the main splice are connected to the battery positive. They are always hot!
How the alternator supplies and gets power:
When the engine is running the ignition needs power.
Current flows from the high voltage power supply, the alternator, through the key switch to the ignition.
The voltage regulator senses the voltage in the blue wire (labeled J2B).
Inside the regulator is basically a switch. Opening and closing the switch makes and breaks power to create the electromagnetic field inside the alternator.
More about the isolated-field alternator here: Identifying Chrysler Alternators (1960-1976)
Paul,
The heavy gage black wire is alternator output.
Lets break this up by first covering what the black wire does. Then we'll cover what the other two alternator wires do.
Cars have two power sources: Battery & Alternator.
Power flows from whichever one can supply at the higher voltage.
> Battery can supply power at approximately 12.5 Volts.
> Alternator can supply power at approximately 14 Volts when its running.
The output wire from the battery and the one from the alternator are joined at the main splice. From that junction power is fed to the key switch, fuse box, headlight switch.
In the illustration below the main junction is represented by a solid black dot.
All of the wires joined at the main splice are connected to the battery positive. They are always hot!
How the alternator supplies and gets power:
When the engine is running the ignition needs power.
Current flows from the high voltage power supply, the alternator, through the key switch to the ignition.
The voltage regulator senses the voltage in the blue wire (labeled J2B).
Inside the regulator is basically a switch. Opening and closing the switch makes and breaks power to create the electromagnetic field inside the alternator.
More about the isolated-field alternator here: Identifying Chrysler Alternators (1960-1976)