×
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 voltage ratio

transformer voltage ratio

transformer voltage ratio

(OP)
Hi,

There is any guideline from ieee or from your experience to set the maximum voltage ratio for a distribution transformer? I need to decide if install a 33 kV / 0.4 kV 2 MVA transformer or run a 4.16 kv cable from a 500 m away substation, and install a 4.16 kV / 0.4 kV 2 mva transformer.

Please advice,

Regards

RE: transformer voltage ratio

33kV to 433/415V is pretty standard for a distribution transformer in Australia. The 33k/433 will likely also be cheaper, smaller and more efficient than the 4.16k/433 as the HV current is a lot lower on the 33kV.
No experience with the cost of cabling for the 500m at the different voltages though so you would have to factor that into your decision making.

RE: transformer voltage ratio

What are your company/utility plans for the 4.16 kV system? Are you keeping both voltages for the foreseeable future? Or do you have plans to retire the 4.16 kV system?

The definition of 'foreseeable future' would be the present value of the 4.16 kV installation plus the present value of the future event to replace it. If that event is far enough out, its PV approaches zero.

RE: transformer voltage ratio

A 33kV breaker is significantly more expensive than it's 4160V counterparts and the protection is likely to be more sophisticated and costly. These factors may offset or completely negate the additional cost of 500m of MV cable.

RE: transformer voltage ratio

(OP)
Scotty you are right,

Actually the feeder in 33 kV is more costly than the 2 MVA transformer. Regards

RE: transformer voltage ratio

Also load losses of 33/0.433 kV and 4.16/0.433 kV transformers will be almost same, infact it may be slightly high for 33/0.433 KV as mean turn dia of HV will be bit more.

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