When back feeding a Step Down Transformer to achieve a higher voltage how should the neutral and grounding and bonding be addressed since the neutrals ls on the secondary side originally but now will be on the primary side

 

How the neutral connection (if there is one) is wired depends on the transformer type and feed.
http://www.allaboutcircuits.com/tex...ent/chpt-10/three-phase-transformer-circuits/

http://ecmweb.com/code-basics/grounding-and-bonding-separately-derived-systems
http://iaeimagazine.org/magazine/2009/11/16/separately-derived-systems/

 

How the neutral connection (if there is one) is wired depends on the transformer type and feed.
http://www.allaboutcircuits.com/tex...ent/chpt-10/three-phase-transformer-circuits/

http://ecmweb.com/code-basics/grounding-and-bonding-separately-derived-systems
http://iaeimagazine.org/magazine/2009/11/16/separately-derived-systems/

I was referring to the standard 480-volt Delta to 120 208 y Dry type Transformers normally used in commercial facilities to step down power
After reading the information you suggested I do understand we need a 480-volt Wye 120 208 y or Delta so that when we feed the Transformer with the 208v 3p power we will have a 480v neutral on the secondary side to refeed the existing 480-volt electrical panel.
Thanks

 

What are you feeding from the 480 secondary that requires a neutral?
Do you actually need a neutral?
Max.

 

What are you feeding from the 480 secondary that requires a neutral?
Do you actually need a neutral?
Max.

Yes there are some 277 lighting circuits being feed from the existing 480-volt panel.

 

Are you splitting the 480v loads across the three 480v phases?
Look under Uncommon Service section.
http://www.ccontrolsys.com/w/Electrical_Service_Types_and_Voltages
Max.