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

Step-up transformer Wattage?

Step-up transformer Wattage?

Step-up transformer Wattage?

I bought a 110v wall-mounted AC which I plan to use overseas where (mostly) only 220-v sources are available. The box says 5200 BTU rating. It also says the eff. is 9.7 What minimum transformer wattage do I need? Please show calc. Thanks.


RE: Step-up transformer Wattage?

You need to look on the unit or its manual and find the specifications for maximum current required (amps).  

Take the maximum current and mutiply by 120.  Now increase that number by about 15%.  That will give a rough guide to a minimum transformer size.  

But as noted in some recent threads, if your A/C unit is designed for 60 Hz, don't expect it to work properly on 50 Hz, since motor speeds will be reduced.

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


White Paper - PLM and ERP: Their Respective Roles in Modern Manufacturing
Leading manufacturers are aligning their people, processes, and tools from initial product ideation through to field service. They do so by providing access to product and enterprise data in the context of each person’s domain expertise. However, it can be complicated and costly to unite engineering with the factory and supply chain. 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