Originally Posted by TECHguy

I believe Wye motors are more efficient and offers higher RPMs but moderate HP or thrust. When greater horsepower is required to drive your load, a delta connection is more common. There are wye-delta motors out there where the wye connection is used for starting means and then switches to a delta connection to provide horsepower.

Wye connected power has two different voltages available. The Phase to Phase voltage is the main system voltage (typically 208 VAC or 480 VAC in the United States). The Phase to Neutral voltage is also available, and is typically used for small single phase loads (120 VAC or 277 VAC).

Delta connected power only has a single voltage level available: the Phase to Phase voltages. Other voltages can be obtained only by using step-up or step-down transformers.

I hope I have assisted with your question!