Need Help! Is my transform wired correctly?


Results 1 to 7 of 7

Thread: Is my transform wired correctly?

  1. #1
    Member
    Join Date
    Nov 2006
    Location
    usa
    Posts
    33
    Downloads
    0
    Uploads
    0

    Default Is my transform wired correctly?

    Sorry to ask such a simple question but I'm trying to cover all my basis. I have a new to me CNC mill with unknown history. It has a transformer that needs to be wired based on input voltage. It was setup for 208 single, and mine is coming in at 249. I'm asking this cause I'm getting some weird voltage readings throughout the cabinet where I feel I should be getting 120. The following diagram is how I have it wired and what the output voltages are. Why is the reading from E-OV 99? shouldn't it be 0? I'm seeing these half voltages throughout the cabinet. Funny thing is most of the machine is working. I'm trouble shooting a spindle issues and I need to take this transformer off the list.


    Thanks.








    Is my transform wired correctly?-trans-jpg










    Is my transform wired correctly?-screenshot_20201124-175538_gallery-jpg

    Similar Threads:
    Attached Thumbnails Attached Thumbnails Is my transform wired correctly?-trans-jpg   Is my transform wired correctly?-screenshot_20201124-175553_gallery-jpg   Is my transform wired correctly?-screenshot_20201124-175538_gallery-jpg  


  2. #2
    Member machinehop5's Avatar
    Join Date
    Aug 2009
    Location
    United States
    Posts
    1564
    Downloads
    5
    Uploads
    2

    Default Re: Is my transform wired correctly?

    ...What about the Interconnects..can't see them in the photo. 208v input would have had a H4 to H10 jumper..Did you remove it..?



  3. #3
    Member
    Join Date
    Nov 2006
    Location
    usa
    Posts
    33
    Downloads
    0
    Uploads
    0

    Default Re: Is my transform wired correctly?

    There is two jumpers both the dark and light green in the first photo.



  4. #4
    Member
    Join Date
    Nov 2006
    Location
    usa
    Posts
    33
    Downloads
    0
    Uploads
    0

    Default Re: Is my transform wired correctly?

    Ohh the actual wires have been removed and replaced with drawn, so its easier to see.



  5. #5
    Member machinehop5's Avatar
    Join Date
    Aug 2009
    Location
    United States
    Posts
    1564
    Downloads
    5
    Uploads
    2

    Default Re: Is my transform wired correctly?

    Quote Originally Posted by funford View Post
    There is two jumpers both the dark and light green in the first photo.
    ...your drawing looks correct for 240v.



  6. #6
    Member
    Join Date
    Nov 2006
    Location
    usa
    Posts
    33
    Downloads
    0
    Uploads
    0

    Default Re: Is my transform wired correctly?

    Are the output measurements correct? Is E to Ov suppose to have voltage? I thought ov was neutral and e was earth ground. But have know idea if a transformer like this is suppose to read such.



  7. #7
    Community Moderator Jim Dawson's Avatar
    Join Date
    Dec 2013
    Posts
    5716
    Downloads
    0
    Uploads
    0

    Default Re: Is my transform wired correctly?

    If you are measuring from the terminal to earth ground (E) or cabinet ground, you may get some erroneous readings. You need to measure leg to leg. The leg to leg output voltages are what I would expect, 42 and 122

    Jim Dawson
    Sandy, Oregon, USA


Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Is my transform wired correctly?

Is my transform wired correctly?