Fault Current

I have a central power distribution panel (PDP) on my farm being fed with a 25KVA 7200/240v transformer by my utility supplier. I recently provided power to a new remote building (1200ft away) by using two 7200/240v 50KVA transformers. The first is fed with a 200a breaker using 20' of 4/0 alum 240v at the PDP stepping up the voltage to 7200V (center tap is not used). Then 1200' of 1/0 15K wire is buried to the second transformer where the voltage is dropped back down to 240V and feeds a 200a panel through 80' of 4/0 alum direct bury (Everything works perfectly). My question is this. Have I affected my fault current at my central PDP by this?
asked 12/23/2014

2 Answers

From reading your description, I don't believe you would have affected the fault level at the PDP.  The fault level is mainly a function of the upstream system, not the downstream (which is what you have changed). 

You may need to look at how the protective devices are working to satisfy yourself that there are no issues. 

answered 1/9/2015 Steven McFadyen 246
Steven McFadyen

Yes, you have effected it.

answered 2/3/2015 koti 2

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