That I remember I never did. Your 3 phase 480 volt is the feed and on the secondary you DERIVE your neutral, if needed to the load.I am feeding a 480 delta- 208/120 wye transformer from a 480 wye source. Is there a code article that would require a neutral to be pulled with the phase conductors to the transformer?
A delta - wye transformer will not need a neutral on the supply and only needs a neutral on the load side if you want to.I did not think the transformer needed it, but thought I might be missing a code requirement to pull it. I understand that I will be deriving a neutral on the transformer.
No problem feeding 480 delta transformer from 480 wye service- correct?BBQ said:A delta - wye transformer will not need a neutral on the supply and only needs a neutral on the load side if you want to. A wye - wye transformer would require a neutral on the supply side and only needs a neutral on the load side if you want to.
Why wye? Wye primaries are often used on large substation class transformers. 1 reason is the closer you get to the star point the lower your voltage is to ground therefore requiring less insulation and the windings can be closer to the transformer can. Another reason is that by having the neutral it gives you more options for your protective relaying of the transformer. Wyes also handle unbalanced loads better which for all these reasons that pretty much all utility generators are wye connected.
I once saw a wye to wye transformer used in an inverter setup on a solar array we installed. I don't know what its purpose was or reason for being wye was though.Honestly said: