×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Wye-Wye Neutral and Equipment Grounding

Wye-Wye Neutral and Equipment Grounding

Wye-Wye Neutral and Equipment Grounding

(OP)
I would like to obtain everyone's comments on the transformer we perceived to be grounded.

The transformer is a 10 MVA 34.5 - 0.60 kV, Wye-wye with both primary and secondary neutrals grounded effectively. The primary supply side is also connected to a secondary Wye with neutral grounded. The secondary neutral is serving line-neutral loads.

We have used a dedicated return conductor from the transformer to the primary supply side. We used Equipment Grounding conductor to interconnect the equipment as shown...I would like to obtain anyone's comment in case we forgot something.

RE: Wye-Wye Neutral and Equipment Grounding

If I understand your drawing correctly it looks like the neutral is grounded at the transformer secondary and also in your disconnecting equipment. Don't know where you're located but I believe the NEC would prohibit this unless it's a utility owned transformer.

RE: Wye-Wye Neutral and Equipment Grounding

(OP)
I apologize for the confusion wroggent, the neutral is not grounded at the disconnecting means and so the slash green marks indicates deletion of the connection of the neutral to ground at the disconnecting means.

My doubt is how the SBJs (supply bonding jumpers) are connected at both primary and secondary wye points.

Thanks

RE: Wye-Wye Neutral and Equipment Grounding

(OP)
To add, if the primary and secondary zero sequence network of the wye(grounded)-wye(grounded) transformer are tied up and connected to the primary supply system, assuming the supply is also wye(grounded) how can we set the relays to be discriminate as to the location of the fault (primary and secondary)?

RE: Wye-Wye Neutral and Equipment Grounding

Is this a utility transformer? Or customer owned under the NEC?

RE: Wye-Wye Neutral and Equipment Grounding

(OP)
It is customer owned

RE: Wye-Wye Neutral and Equipment Grounding

(OP)
I received information that the transformer is utility supplied and owned

RE: Wye-Wye Neutral and Equipment Grounding

If utility owned than the neutral must be tied together and at the grounding system as well in the transformer.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources