Wiring 3 phase transformer

[Smart $]

I'm guessing that somewhere in the annuls of transformer wiring there's a note that says midpoints of three windings are an XO and midpoints of a single winding are X4.

X0 is not the midpoints of three windings. It is a common connection of one end of each of three windings, also known as a wye configuration of the windings.

X4 is used for three phase transformers to denote it is a midwinding tap of one of the three windings which are delta configured. Yet a single phase transformer with a midpoint winding tap terminal is not marked X4. Also, if you have a two-winding secondary, single phase transformer, the terminals are typically denoted as X1, X2, X3, and X4... so X4 does not exclusively denote a midwinding tap.

 

[augie47]

At first I thought that but Smart is good at hitting me with stuff from left field.

you were saying

 

[Steviechia2]

Thanks

 

[noelelectric]

always h.. are primary site and x... are secondary site

always h.. are primary site and x... are secondary site

X4 is typically a mid-winding tap... and definitely not the same as X0;i agree with u.
h1.h2.h3 is for 208 volts(primary is'nt low o higt volts,its just your conexion source) and x1 x4 x2 x3 are secundary site,you have two coil x1 and x2; x3 x4,thats is if you want to make paralle conexion with other trasnmformer ore series to use 480 volts,and remember on 480 volts u dont need a neutral.