2 Phases of a 3 Phase System

[GoldDigger]

That's what I figured; would it be to the right or to the left (+ or - 90 degrees) of the A-N waveform?

Draw the vectors on the delta drawing.
Once you specify rotation direction of coordinate system the answer follows.

 

[Smart $]

Depends on your reference and rotation.

With positive rotation starting with A, we have A at 0 degrees, B at 180 degrees and C at 270 degrees.

So, C lags A by 270d and C lags B by 90d. Also, C leads A by 90d and C leads B by 270d.

Ummm.... the center tap is between terminals A and C under the NEC.

 

[mivey]

Ummm.... the center tap is between terminals A and C under the NEC.

Then use negative rotation and swap "B" and "C" in my post and you will be happy that the phase letters then match the NEC letters you prefer.