×
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

ETAP Star Simulation Values are incorrect

ETAP Star Simulation Values are incorrect

ETAP Star Simulation Values are incorrect

(OP)
Hello,

I just created a star coordination in ETAP, but it seems that all displayed values are being transformed through my transformer turns ratio.

The simulation is very simple: 25kv overhead electrical service into a 25kv/600v 1000kVA transformer with primary fusing. On the secondary there is a 1200a CB feeding an MCC.

When I generate my star diagram, my current values in the plot labels for the transformer and anything downstream seem to be inflated by about 41 times (transformer turns ratio). Is there any way to fix this so that my coordination devices reference primary current instead?

The image below should show you what I mean. For instance, my transformer inrush is displayed at 8xFLA which should be 23x8=184amps, but it shows 7698 amps. Same with Primary FLA and the MCC pickup current.

RE: ETAP Star Simulation Values are incorrect

Verify your transformer model. Voltages might be swapped in the data entry.
provide screen shot of raring page.

RE: ETAP Star Simulation Values are incorrect

(OP)
Hi Sindhuk,

Here is my rating page:

RE: ETAP Star Simulation Values are incorrect

try this under the plot options -> devices -> transformer. Change the source and protection secondary


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