Yes Y means wyeeeeeeeeeeeeee configuration versus the other DELTA configuration.
YOUR QUESTION: BTW, at our tech college all three legs are 110 to neutral. We don't have a hot leg. How would that work? What would it read phase to phase?
ANSWER: if you have three legs ALLLLL of which read 120 to Neutral thats a 208 Y 120 Volt Three Phase Four Wire configuration THERE IS NOOOOO RED OR HIGH 208 VOLT LEG TO "NEUTRAL". On that system its 208 (120 x square root of 3) line to line but only 120 ANY line to Neutral.
NOTE if the system is a 120/240 Volt Three Phase Four Wire Cenetr Tapped (only one winding tapped) DELTA known as a Red Leg or High Leg system,,,,,,,, Its 120 volts to Neutral on ONLY TWO of the legs (the 2 legs on the center tapped transformer) BUT ITS 208 ON THE HIGH/RED LEG TO NEUTRAL......
YOUR STATEMENT: To the world...when hooking up single phase equipment to three phase power make sure you use the two lower legs. There is "always" one that is hotter than the other two and you should leave that one out. This is extra imporant when working with machines with transformers (ie welders)
CLOSE BUT NO CIGAR: Its NOT "always" theres one "hotter"...... On the 208 Y 120 system ALLLLLL legs are the same and alllllll are 120 to Neutral and its 208 any line to any other line. HOWEVER on the 120/240 volt three phase 4 wire Delta yesssssssssssssss one leg is "hotter" as its 208 to neutral while the other 2 are 120 to Neutral
NOTE its also common to use a 240 or 480 volt STRAIGHT NON CENTER TAPPED DELTA. Thats called Three Phase THREE Wire DELTA. 240 line to any other line, you can use it to feed 240 single phase loads or 240 three phase loads
Got it now????????