Transformer Connections

[ianis]

Reading through the archive I saw that it shows transformer connections made as follow X1-Black, X2-Red , X3-Blue, Xo- Ground/Neutral. I have always seen them them X1-Red, X2-Black, X3-Blue, Xo-Ground/Neutral. Are both colour markings correct?

 

[Bea]

Does not make a difference of color coding so long as you maintain color coding for the two different nominal voltage IE 120/208 and 277/480 NEC 210.5. Although I would say that typically A-Black-X1, B-Red-X2, and C-Blue-X3 is the standard for 120/208.

 

[brian john]

Are both colour markings correct

Based upon your spelling of COLOR/COLOUR are you located in the continetal US?

 

[jim dungar]

Does not make a difference of color coding so long as you maintain color coding for the two different nominal voltage IE 120/208 and 277/480 NEC 210.5. Although I would say that typically A-Black-X1, B-Red-X2, and C-Blue-X3 is the standard for 120/208.

There is NO standard color code for identifying the phasing of conductors. Color codes seem to be regional or even local.

 

[Bea]

There is NO standard color code for identifying the phasing of conductors. Color codes seem to be regional or even local.

I think I used the word typically in my post

 

[ianis]

thank you ...

 

[ecirplr]

Reading through the archive I saw that it shows transformer connections made as follow X1-Black, X2-Red , X3-Blue, Xo- Ground/Neutral. I have always seen them them X1-Red, X2-Black, X3-Blue, Xo-Ground/Neutral. Are both colour markings correct?

There was a national color code up until 1968 is what I have been told.Before '68 it was Bk/R/BL(120/208) and Br/Or/Y(277/480). Wht was used as neutral for both systems generally. This is why most journeyman think that there is a national color code and have difficulty when working in localities with different color codes.