| Terminal | Definition | Notes |
| A | Battery | Battery positive connection |
| B | Battery | Battery positive connection |
| B+ | Battery | Battery positive connection |
| C | Center | Centre point of a Y stator |
| COM | Computer | Computer Connection |
| D+ | Warning light | Comes from the old ‘Dynamo Positive’ on a generator |
| DFM | Dynamo Field Modulation | Duty Cycle signal from the ECU |
| E | Warning light | Comes from the word ‘Excitation’ |
| F | Field | For externally regulated alternators |
| FR | Field Regulation | Voltage Signal from the ECU |
| G | Ground | Chassis negative connection |
| I | Indicator | Warning Lamp |
| L | Lamp | Warning Lamp |
| M | Field | Found on older Externally Regulated units |
| N | Neutral | Centre point of a Y-connected stator |
| P | Pulse | Stator connection for tachometer |
| R | Relay | Output to charge relays, etc |
| S | Sense | Battery Voltage sense wire |
| S (FORD) | Stator | Stator Pulse. Used for tachometers |
| T | Tach | Stator Pulse. Used for tachometers |
| W | Waveform | Stator Pulse. Used for tachometers |
12 Comments
js
Love it. thanks
Steven D Harris
Thanks - useful today for me! 12/27/2020.
Bob
I have a question I have terminal letter N on my alternator along with terminals B I and F. Those three I terminals are fine. The terminal N is my question? Can you help me?
Bob
I have a question I have terminal letter N on my alternator along with terminals B I and F. Those three I terminals are fine. The terminal N is my question? Can you help me?
Yoneda Jr Kloulubak
can I send you a picture of an 24v alternator and ask you to identify whether it's an internal or external regulated unit and also can you tell me where to connect each terminal ? This unit is most likely rebuilt and no connection instructions comes with it and vendor can't do much to help me. Thanks so much.
Johannes Åkrehamn
IG to ignition
Hammer
Good itechnical information
Jim K
Thank you so very much, straight and to the point, and I don't need to be a college professor to understand it. If only all things I need to look up were this simple.
Vasant Ichharamp
Very informative
Peter Sprunk
Hello Peter, greetings to you from Gympie in Australia! One of your Terminal Descriptions ... E = Warning light - Comes from the word ‘Excitation’ ... seems to be only half-right or maybe even incorrect. (See your website address below.) In an alternator wiring diagram I have, it certainly is not a warning light. The connection E appears to be the negative connection for the rotor coil in an alternator. Presumably that is then taken to be the exciter coil, hence the E. Or could E also stand for E = Earth? A friend (in Papua New Guinea) and myself (in Australia) came across this while trying to work out how to connect a Sterling Alternator Regulator; but we can't work out where exactly the two black wires go. Or better put, we worked that out, but we are not sure now whether the the E & N terminals on the alternator need to be connected to Earth, i.e. ground (B-). Various auto and marine electricians I have asked in my area don't seem to know anymore either. If you were interested, I could send you a photo of the diagram. https://shop.pkys.com/Alternator-Terminals-explained.html
Shane Chambers
F (Field ) = IG (Ignition) Would be nice to see a matrix of synonymous connectors. There seems to only be a handful, and yet everyone seems to want to 'roll their own' nomenclature. All these Engineers should have a pow-wow and and standardize the naming conventions. Should be something like BP/+ = Battery Positive. BN-/CG = Chassis Ground IG = Ignition
James Nicholas
Hello, I have noticed that in some applications R is used as signal tep for Tachometer is it so.
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