×
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

transformer

transformer

transformer

(OP)
problem that I had at work was I lost 1 of my 12470 to 480 transformers on the pole well I had another set in the power center after 12470 steped to 4160 so 4160 in it was hook wye with 5 taps on the primary most i could get out of it was 365 phase to phase at the time I couldn't remember how to hook it delta the secondary just had 3 bars for each phase couldn't change it there so i was wondering if I could have got 480 if I would have hooked it delta on the primary  
 

RE: transformer

Sentences? Punctuation? Is there a question?

RE: transformer

We are trying to understand what you are trying to do.
Is this correct? :
A 12.47 kV - 480V transformer failed.

You also have a 12.47 kV- 4.160 V service and a transformer that puts out 385 volts when connected in a wye on the primary configuration to an unknown primary voltage source (12,470V, 4160V, 480V?).

You want to know what the voltage would be if you connected it in delta on the same unspecified primary voltage.

Switching the transformer primry connection from wye to delta will raise the output voltage by  sqroot 3 = 1.732. (Assume no change on the secodnary wiring.)

1.732 x 385V= 666V.  Even dropping 10% on the taps only gives 600V.

If you have any nameplate data on your available trasnformers and a better descriptionof what you are trying to do, we may be able to offer some guidance.
  

RE: transformer

(OP)
Yes rcwilson sorry for the way I posted it.Name plate is pretty rough hard to make out what is on it. I could see 4160/480 delta. The output connected wye may have been lower, after 15 hours and working in the rain I really didn't care,all I know I didn't see close to 480!

So your telling me for it to even be possible the most I could have saw was around 310 volts phase to phase on the secondary with the primary connected wye?

RE: transformer

Sounds like you had a rough day! But I still don't have an answer for you.

A 4160-480 V transformer is probably connected delta-delta. A wye connection on the 4160 V would be unusual.  4160V phase-phase is 2400 V phase-neutral.  2.4kV used to be a common industrial voltage. A 3-phase transformer with three 2400V-480V windings can be wired delta-delta for 480V delta output with 2400V  primary or wye-delta for 480V output on a 4160V primary.

I can't envision how the 380V phase-phase output occurred unless there is a transformer problem.

Switching from wye primary to a delta primary connection will increase the secondary delta phase-phase voltage by a 1.732 factor (Square root of 3).

If you took that same 380V output and were able to rewire the secondary connections in wye, you would get about 600V phase-phase, 380V phase-neutral (great for Canadian industry but not much use to you.)

Sounds like its time for a new 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