Transformer Impedance definition

[Freshsurfer]

Hi, I`m working on a 4.16/0.48kV 500kVA transformer specification. Who defines the impedance for it? exist an IEC standard for this?

 

[waross]

In North America it is the voltage or the PU of rated voltage that will drive rated current through a bolted fault on the secondary as determined by an actual test.
Selecting an impedance for a new transformer. Consider the Available Short Circuit Current and the ASCC rating of the switch gear. You may also consider Arc Flash issues.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[JuanBC]

Hi.

Take a look at the picture attached. It is from IEC 60076-5.
GL

JBC
.......
"The more I read, the more I acquire, the more certain I am that I know nothing"

 

[JuanBC]

Also take a look at this:

https://www.eng-tips.com/viewthread.cfm?qid=440427

JBC
.......
"The more I read, the more I acquire, the more certain I am that I know nothing"