Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: Same xfrmr feeding 2 diff swiches

  1. #1
    Join Date
    Sep 2012
    Location
    NJ
    Posts
    2,015

    Same xfrmr feeding 2 diff swiches

    Scenario, same xfrmr feeding two different switches.

    Building 22 switch being feed with 4 sets of #500 & 1 #1/0
    Building #23 switch being feed with 5 sets of the same size wires.

    To me it looks( the dot) like they are calling for either feeder to be tapped. I know you can’t run the sets for both switches from the xfrmr, meaning it can’t directly feed them so it has to be a tapped, correct? Could one one Ilsco tap blocks for this application? Seems a bit tricky. Need a big tap box as well. Thanks.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	FEEDERS 1.jpg 
Views:	71 
Size:	12.2 KB 
ID:	20338   Click image for larger version. 

Name:	FEEDERS 2.jpg 
Views:	67 
Size:	10.8 KB 
ID:	20339  

  2. #2
    Join Date
    Aug 2004
    Location
    Northern illinois
    Posts
    16,692
    Quote Originally Posted by mstrlucky74 View Post
    Scenario, same xfrmr feeding two different switches.

    Building 22 switch being feed with 4 sets of #500 & 1 #1/0
    Building #23 switch being feed with 5 sets of the same size wires.

    To me it looks( the dot) like they are calling for either feeder to be tapped. I know you can’t run the sets for both switches from the xfrmr, meaning it can’t directly feed them so it has to be a tapped, correct? Could one one Ilsco tap blocks for this application? Seems a bit tricky. Need a big tap box as well. Thanks.
    I don't see why the connection cannot be made right at the transformer. Whether it is a legal tap or not is something else that IMO is not dependant on whether the connection is made at the transformer..
    Bob

  3. #3
    Join Date
    Feb 2003
    Location
    Illinois
    Posts
    23,581
    You can have multiple sets of conductors running from a transformer. Is the transformer located outside? If not, you will be limited by the 25' rule in 240.21(C)(6). If the transformer is outside the rule in 240.21(C)(4) will apply permitting unlimited conductor length as long as the installation complies with all of the rules in that subsection.
    Don, Illinois
    Ego is the anesthesia that deadens the pain of stupidity. Dr. Rick Rigsby
    (All code citations are 2017 unless otherwise noted)

  4. #4
    Join Date
    Sep 2012
    Location
    NJ
    Posts
    2,015
    Quote Originally Posted by petersonra View Post
    I don't see why the connection cannot be made right at the transformer. Whether it is a legal tap or not is something else that IMO is not dependant on whether the connection is made at the transformer..
    9 sets leaving xfrmr?? Where the hell would all the conductors terminate?

  5. #5
    Join Date
    Aug 2004
    Location
    Northern illinois
    Posts
    16,692
    Quote Originally Posted by mstrlucky74 View Post
    9 sets leaving xfrmr?? Where the hell would all the conductors terminate?
    I didn't say it was practical just legal. Besides most of the time you can get stackable connectors
    Bob

  6. #6
    Join Date
    Feb 2003
    Location
    Illinois
    Posts
    23,581
    Quote Originally Posted by mstrlucky74 View Post
    9 sets leaving xfrmr?? Where the hell would all the conductors terminate?
    T&B has various adapters for transformer connections that permit up to 16 sets of conductors.
    Don, Illinois
    Ego is the anesthesia that deadens the pain of stupidity. Dr. Rick Rigsby
    (All code citations are 2017 unless otherwise noted)

  7. #7
    Join Date
    Sep 2012
    Location
    NJ
    Posts
    2,015
    Quote Originally Posted by don_resqcapt19 View Post
    T&B has various adapters for transformer connections that permit up to 16 sets of conductors.
    Wow. How can I get a pic of how those connections look inside xfrmr? Thanks

    Sent from my SM-G955U using Tapatalk

  8. #8
    Join Date
    Jun 2004
    Location
    Cherry Valley NY, Seattle, WA
    Posts
    4,315
    You could use something like this with one on each side of the spade for 16 terminals.
    Attached Images Attached Images  
    Ethan Brush - East West Electric. NY, WA. MA

    "You can't generalize"

  9. #9
    Join Date
    Sep 2012
    Location
    NJ
    Posts
    2,015
    Quote Originally Posted by electrofelon View Post
    You could use something like this with one on each side of the spade for 16 terminals.
    But still don't understand how it's possible to come out of the xfrmr with 16 sets of 4". Does not seem like there would be enough room for all those conduits/flex to terminate on the enclosure.

  10. #10
    Join Date
    Sep 2012
    Location
    NJ
    Posts
    2,015
    Quote Originally Posted by electrofelon View Post
    You could use something like this with one on each side of the spade for 16 terminals.
    But still don't understand how it's possible to come out of the xfrmr with 16 sets of 4". Does not seem like there would be enough room for all those conduits/flex to terminate on the enclosure.

    Sorry I have 9 sets 4".

Posting Permissions

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