Results 1 to 7 of 7

Thread: another utility distribution question - location of auto tap changer

  1. #1
    Join Date
    Jun 2004
    Location
    Cherry Valley NY, Seattle, WA
    Posts
    4,392

    another utility distribution question - location of auto tap changer

    This seems odd. Wouldn't you put an auto bank with tap changer downstream a ways after you built up some load and loss? Why put one right at the sub?
    Attached Images Attached Images  
    Ethan Brush - East West Electric. NY, WA. MA

    "You can't generalize"

  2. #2
    Join Date
    Jan 2016
    Location
    PA
    Posts
    5,701
    on long lines with heavy concentrated loads they do install remotely

    the primary purpose of station mntd is load regulation, diurnal, weekends, etc
    The difference between genius and stupidity is that genius has its limits.

  3. #3
    Join Date
    Jun 2004
    Location
    Cherry Valley NY, Seattle, WA
    Posts
    4,392
    I just dont recall seeing them at the substation. BTW, my OP was worded poorly "....downstream a way after you built up some load" obviously the most load occurs at the beginning of the circuit.....y'all knew what I meant.
    Ethan Brush - East West Electric. NY, WA. MA

    "You can't generalize"

  4. #4
    Join Date
    Jan 2016
    Location
    PA
    Posts
    5,701
    most of the time the loads are radial
    you would need one on each branch
    but one can serve all at the sub

    each line is sized adequately for vdrop
    but when all are loaded you get drop out of the xfmr
    and rise when unloaded
    more designed to compensate for xfmr drop
    The difference between genius and stupidity is that genius has its limits.

  5. #5
    Join Date
    Nov 2007
    Posts
    843
    Quote Originally Posted by electrofelon View Post
    I just dont recall seeing them at the substation. BTW, my OP was worded poorly "....downstream a way after you built up some load" obviously the most load occurs at the beginning of the circuit.....y'all knew what I meant.
    My experience is to install capacitors at end of lines for voltage improvement--> big loads at the end of lines! Tap-changer is built in the substation transformer.

  6. #6
    Join Date
    Jun 2004
    Location
    Cherry Valley NY, Seattle, WA
    Posts
    4,392
    Bonus: I was able to get a pic of the tap position. Wish I could read that label, not quite the right angle.
    Attached Images Attached Images  
    Ethan Brush - East West Electric. NY, WA. MA

    "You can't generalize"

  7. #7
    Join Date
    Jun 2004
    Location
    Cherry Valley NY, Seattle, WA
    Posts
    4,392
    Quote Originally Posted by Ingenieur View Post
    most of the time the loads are radial
    you would need one on each branch
    but one can serve all at the sub

    each line is sized adequately for vdrop
    but when all are loaded you get drop out of the xfmr
    and rise when unloaded
    more designed to compensate for xfmr drop
    Makes sense to compensate for sag off the sub transformer. I guess the sub tranny doesnt have a tap changer built in?

    Here is an example of more what I am used to. This is the line that serves my house. From substation goes about 5 miles on 7.62/13.2 then is dropped down to 4800 to feed the older lines. From there, its about 4 miles to my house. There is an auto tap changer about halfway on the 4800 line. That makes sense to me. Even have a picture of that one - nothing too exiting but Ill post it.
    Attached Images Attached Images  
    Ethan Brush - East West Electric. NY, WA. MA

    "You can't generalize"

Posting Permissions

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