alternator confusion

[awaffa2003]

ok guys, almost done with wiring up the new engine. but one of my many other electrical issues is that i cant figure out which 3 wires go where on the 3 prong part of the alternator. on the '90 it's easy cuz there's a black connector with all 3 wires inside of it but no such luck with our bikes. help!

[Bob_Roller]

If you are talking about the wires that are on the alternator stator case, the output from the alternator to the diode board, it doesn't make any difference which way the wires are connected .

[awaffa2003]

Really? why not might i ask?

[Bob_Roller]

The output of the alternator, is three phase a/c electricity .

There are six diodes on the diode board, one wire, or phase goes to two diodes for full wave rectification, so the diodes don't care which power they get .

[razz2234]

When I replaced the diode board on mine it said exactly what has been said already...it doesn't matter which wire goes where...

[Barry]

A bit of irrelevant electrical engineering but maybe of interest to some.

A 3 phase alternator may be considered to be like a 3 phase motor in reverse. The connections to a motor do matter in that if you swap two of the phase connections it will reverse the direction of the rotating magnetic field and the motor will turn the other way.

A 3 phase AC alternator being used to provide DC via a diode board can in principle be rotated in either direction and still work. That is the underlying reason why the order of connection on our airheads doesn't matter.  If the 3 phase output from the alternator were used to power a 3 phase motor the order would matter.