High Leg Delta

[SG-1]

I believe the xfmr is improperly taggd.

'0' is reserved for the neutal-connection where by definition the "neutral conductor" is the one that usually is grounded and has equipotential (excluding phase displacement) measurements from every other conductor. Therefore, although the center-tap of one winding with regard to the two terminals of the same winding of a "red", "high", "bitch", etc-leg delta connection, is technically correct... there is no equipotentil measusurement from all other conductors!

The term "neutral" is used by convention, simply for the lack of a better term. When used in single-phase 3-wire circuits, the term "neutral conductor" is correct.

In 3-phase, 3-wire circuits, there is a "neutral point" that meets the definition above for both the conventional wye and delta-derived systems. In the former, the neutral point is a "physical" one. In the latter, there is no "physical" neutral point, but there is a "virtual' one, namely the centriod of the triangle.

For 4-wire, wye-connected circuits, the "neutral point" is usually "grounded", hence its distribution conductor becomes the "neutral conductor". But, for 4-wire delta-connected circuits like the "grounded-corner" and "mid-point grounded" (both unusual in European practice) the definition is not met. However, by USA convention the "grounded conductor" is labeled the "neutral conductor"! Phew!

Regards, Phil Corso,

Phil, I follow you except the first line. The NP does not have any "0". It has a "GND".

 

[kwired]

Phil, I follow you except the first line. The NP does not have any "0". It has a "GND".

And that may be because it comes bonded to the frame, case, enclosure, etc. If it were isolated and the end user has to bond whichever conductor is to be grounded it very likely would have been marked X4.

 

[Phil Corso]

Kwired... my error!

Phil