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finding leads on 3 phase generators

finding leads on 3 phase generators

finding leads on 3 phase generators

(OP)
I have a procedure to use low voltage DC power source like a battery and a volt meter to ID the leads on a 3phase motor.  For example,  find all the pairs, flash a pair called 1 and 4 and measure the voltage induced in each of the other pairs with a voltmeter.  by the readings identify the other pairs and their polarity in relationship to the first pair which was arbitrarily assigned 1 and 4.

Will this work the same for a 3 phase generator?  I would think so, but since some of you have probably done this a few times, I thought I would ask if there is a better way.  

A related question, I have an old early 60's 75kW 12 lead Kohler set which has two of it's circuits out of order compared to the "normal" wiring diagrams.  For example it is connected series wye 277/480V  with L1=T1-T4+T7-T10=N, L3=T3-T6+T9-T12=N  but L2=T8-T11+T2-T5=N  It works fine, but why do it?  Leads on that one are ID'ed with aluminum bands.  

Thanks

RE: finding leads on 3 phase generators

The generator has two sets of identical windings. They are connected in parallel for low voltage and in series for high voltage. The order in which the windings are connected in series on one phase is reversed. It is equivalent electrically but may be considered sloppy workmanship by some.

Quote (Hyman Rickover):

Why not the best?]
respectfully

RE: finding leads on 3 phase generators

Consider the induced voltages as "Vectors". The result is the same if T2-T5 is interchanged with T8-T11. See drawing below.



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