×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

Transformer supply question

Transformer supply question

Transformer supply question

(OP)

I just had a new transformer installed at 15KVA transformer to add to the existing 25KVA transformer as building was becoming overloaded.

I left the local power company a bunch of cables to play with, but insisted they upgraded the existing line from the 25KVA transformer to cable that can handle 160AMPS at 220V.

I also made them increase the electric meter capacity from 100AMPS to 200AMPS as it was burning under the existing load.

However the terminal box the new electric meter slides into was rated at 100AMPS, so the terminal connections couldn't accept the wire size I had given them which was rated to 160AMPS at 220V.

So they used the 160AMP at 220V cable only on the live wire connection from 25KVA transformer to the electric meter. They then used some much smaller cable with max rating 80 AMPS at 200 Volts to connect the neutral wire from the transformer to the electric meter.

Is this going to cause me problems? They say its ok because its the neutral wire. But I can't believe this.

The 25KVA often is utilized to maximum load which is 100 AMPS so above the cable sizing.

If it won't melt will it increase my electric bill?


RE: Transformer supply question

It's hard to say as I'm not clear on Philippines electrical distribution. Obviously the best bet is at least the same size neutral as the supplies but a smaller neutral could work if most the loads are actually 220V in which case no power or current is added to the neutral. This train of logic only works if you have 110V service Hot-to-Neutral and 220V service Hot-to-Hot.

All of this is a moot point if there is an Authority Having Jurisdiction, inspectors, and local rules to follow.

Or are you talking some sort of power anarchy:




Keith Cress
kcress - http://www.flaminsystems.com

RE: Transformer supply question

I'm glad they knew the safe location for the ladder!

Z

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close