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Thread: Can this 112.5 kVA transformer be in the attic space?

  1. #1
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    Can this 112.5 kVA transformer be in the attic space?

    Hello All,
    The transformer is 112.5kVA 480-208V Delta-Wye 3 phase. It's above the fan-ventilated ceiling. The OCPDs on the primary and secondary are from the readily accessible panels on the floor. I don't think it violates section 450.13(B) because this is an attic (not a hollow space) with light, fan, catwalk and about 6.5' vertical clearance. Will an accessible 'door' required for this transformer and if yes, what size is that door and will a permanent ladder is required?
    Thanks a lot.

  2. #2
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    Looks like no one reads the thread then.

  3. #3
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    As long as your meeting the ventilation requirements of 450.9 and separation requirements of 450.21 (A), I don't think the is a problem with this installation. As far as a door goes, I'm not really sure what your asking? You do have to have access as required in 110.26 (C)(1), but a door isn't required.

    Sent from my SM-G935V using Tapatalk

  4. #4
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    Quote Originally Posted by fandi View Post
    Looks like no one reads the thread then.
    More than 114 did and 2 responded so far.

    JAP>

  5. #5
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    Quote Originally Posted by fandi View Post
    Looks like no one reads the thread then.
    I am sure one of the mods will give you a refund
    Ethan Brush - East West Electric. NY, WA. MA

    "You can't generalize"

  6. #6
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    Quote Originally Posted by fandi View Post
    Looks like no one reads the thread then.
    One nice thing about this forum is people generally only answer if they have something useful or funny to contribute. Or would rather read thru a bunch of useless answers?

  7. #7
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    Quote Originally Posted by Jmccoll77 View Post
    As long as your meeting the ventilation requirements of 450.9 and separation requirements of 450.21 (A), I don't think the is a problem with this installation. As far as a door goes, I'm not really sure what your asking? You do have to have access as required in 110.26 (C)(1), but a door isn't required.

    Sent from my SM-G935V using Tapatalk
    So an access is required per 110.26 (C)(1) but is a permanent ladder required?

  8. #8
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    Quote Originally Posted by fandi View Post
    Hello All,
    The transformer is 112.5kVA 480-208V Delta-Wye 3 phase. It's above the fan-ventilated ceiling. The OCPDs on the primary and secondary are from the readily accessible panels on the floor. I don't think it violates section 450.13(B) because this is an attic (not a hollow space) with light, fan, catwalk and about 6.5' vertical clearance. Will an accessible 'door' required for this transformer and if yes, what size is that door and will a permanent ladder is required?
    Thanks a lot.
    You note that the OCPD's for the secondary are from readily accessible panels on the floor; have you confirmed if you also meet 240.21 for the length of those secondary conductors (240.21(C)(2)), although I'm not sure what your facility is. During design, I always look to see what it would take to replace the transformer in the future as well so access, widths of doors, etc, are also things to take into account.

  9. #9
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    Quote Originally Posted by fandi View Post
    Hello All,
    The transformer is 112.5kVA 480-208V Delta-Wye 3 phase. It's above the fan-ventilated ceiling. The OCPDs on the primary and secondary are from the readily accessible panels on the floor. I don't think it violates section 450.13(B) because this is an attic (not a hollow space) with light, fan, catwalk and about 6.5' vertical clearance. Will an accessible 'door' required for this transformer and if yes, what size is that door and will a permanent ladder is required?
    Thanks a lot.
    Sounds like it meets intent of 450.13(B) more so then if it were above a suspended ceiling.

    If this is an attic and apparently you are in LA area - what kind of ambient temp do you expect in this attic is something to consider and if the transformer can take that while loaded.
    I live for today, I'm just a day behind.

  10. #10
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    Quote Originally Posted by Coppersmith View Post
    One nice thing about this forum is people generally only answer if they have something useful or funny to contribute. Or would rather read thru a bunch of useless answers?
    I'll respond....

    If it's already up there rockin and rollin, why would you want to disturb an already beautiful scenario?


    JAP>

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