Jump to content
Sign in to follow this  
Tony S

Loss of 1Ph to a 3Ph transformer:

Recommended Posts

Tony S

Loss of 1Ph to a 3Ph transformer:

 

So what happens if a 3 phase transformer tries to run on 2 phases?

 

I’ve drawn a 11/.433kV Dyn11 transformer showing the actual phase relationship between primary and secondary windings.

01.jpg.aec70d4f081d07411ed8ef0f28a1eb6a.jpg

 

The LV outputs being:

l1→l2 = 433V

l2→l3 = 433V

l3→l1 = 433V

l1→N = 250V

l2→N = 250V

l3→N = 250V

 

Loose one of the MV primary phases (in this case red) both L3→L1 and L1→L2 become series windings

 

02.jpg.5e0c18f969fd85cecedec8bc4935a655.jpg

 

 

The offload LV outputs now being:

l1→l2 = 0V

l2→l3 = 375V

l3→l1 = 375V

l1→N = 125V

l2→N = 125V

l3→N = 250V

 

 

©Tony S

 


View full knowledgebase

Share this post


Link to post
Share on other sites
Sign in to follow this  

×

Important Information

Terms of UseWe have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.