Delta vs. Wye

[Designer69]

Hey guys, I was just wondering why someone would ever use a delta connected system instead of wye.

From what I've read wye is up to 33% more capacity or something and its safer so why not just get rid of delta?

 

[72.5kv]

The choice of going with delta or wye also depends on the application. In some industrial setting, a shut down from a ground fault is unacceptable so delta system is used or high impedance gounded wye.

 

[charlie]

. . . wye is up to 33% more capacity . . . and its safer . . .

Neither statement is true. The first may be based on heavy single phase load on a delta or the way three phase load hits an open delta. The second statement is not true if all the rules are followed for overcurrent protection. Also, using lights if it is an ungrounded delta.

 

[emahler]

depends on what the POCO provides and cost to convert from a delta to a wye....