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2012 proposed low voltage table

Discussion in 'NESC - ANSI C2 - National Electrical Safety Code' started by stevenal, Feb 12, 2009.

  1. stevenal Well-Known Member

    Is this the most recent version?

    So please help me understand: A 2500kVA 5.3% 277/480 three phase padmount transformer is feeding a panel board. The voltage puts me in column two. Energized work at the panel requires 40 cal/cm^2 from row 3 and note 6. Work at the padmount transformer terminals, however, requires 4 cal/cm^2, from row 4 and note 1. Does this order of magnitude change in IE make sense to anyone?

    Attached Files:

    stevenal, Feb 12, 2009
    #1

  2. acobb Well-Known Member

    Don't know what's up here, but our proposed tables do not match. I have attached the one that I have. Maybe someone else can shed some light on this.

    Alan

    Attached Files:

    acobb, Feb 12, 2009
    #2

  3. stevenal Well-Known Member

    Do the footnotes match?
    I'm guessing my version is more recent, with the inclusion of network systems.
    stevenal, Feb 13, 2009
    #3

  4. jghrist Well-Known Member

    Alan's version is what was presented in the recent APPA Webinar. It treats panels the same as pad-mount transformers.

    Where did your's come from Stevenal?

    As far as I know, these are based on limited tests done by one utility. I understand that IEEE is making additional tests. The actual table that makes it into NESC-2012 may be quite different from either of these. We are not making recommendations based on the proposed table, but are making our clients aware of it.
    jghrist, Feb 13, 2009
    #4

  5. stevenal Well-Known Member

    APPA safety email list in September, prior to voting. Guess Alan's is more recent. Perhaps networks will be adressed outside of the table.

    Know where I might find the footnotes or the whole *.ppt?
    stevenal, Feb 13, 2009
    #5

  6. jghrist Well-Known Member

    You might be able to get it from APPA http://www.appanet.org/ . Since the Webinar was only open to APPA members or for a fee, I assume that it is copyrighted.
    jghrist, Feb 13, 2009
    #6

  7. stevenal Well-Known Member

    So I have the the proposed table which is out for comment. Any ideas on why a footnote describing 50 - 240 V testing is referenced from a cell in the 251 - 500 V column? From the last row.
    stevenal, Oct 5, 2009
    #7

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