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  1. #1
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    Default Looking for an angle

    Four in twelve? So 30 degrees off horizontal, meaning 60 degrees off vertical? What is a reasonable angle to shoot for?

    I'm hoping to solve an electrical problem, by suggesting a change in UL514B, addressing weatherheads. The fascia boards of a gable or I guess a gambrel roof often are used to carry service cable from the weatherhead part of the way down toward a meterbase. UL's Guide Card for these specifies that they are to be installed vertically. When an AHJ enforces this rule religiously, electrical installers in the jurisdiction need to change the angle of the last few inches of cable in order to bring it into the bottom of a vertical service cap.

    The reason for that specification on the guide card is that these caps are tested for moisture-tightness when positioned vertically. Once i come up with an idea of how far off-vertical is reasonably common for weatherheads plonked in line with cable running up the fascia board, I will sound out other STP 514B members about offering an optional alternative to vertical positioning for that test, to allow some weatherheads to be marked for installation up to XXX degrees off vertical.

    I don't think it's reasonable to leave the angle up to each manufacturer: just too complicated for a UL standard. So, what angle would you suggest: 45 degrees off vertical? 60 degrees off vertical? Less? More?

    Thanks

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  2. #2
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    Default Re: Looking for an angle

    Define "vertical".

    Find out just how "vertical" the manufacturers use for their designs: dead-on 90? "vertical" or some tolerance from that..

    Is a "vertical section of panelboard "90? dead-on vertical"? Or are vertical sections of panelboards just "not horizontal", and is "horizontal" "dead-level"?

    Jerry Peck
    Construction Litigation Consultant - Retired
    www.AskCodeMan.com

  3. #3
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    Default Re: Looking for an angle

    Fun questions, Jerry, though I'm not sure how well the answers will speak to weatherheads.
    I suspect that commodity panelboards, including those installed in residential and small commercial settings, are not assembled by humans but by automated machinery. If this surmise is correct, there would be little tolerance indeed. Because cabinet covers have to line up with both the cabinets and the breakers or other devices attached to and therefore located by the busbar stabs, This should be quite standard too. Of course, "should" . . . .

    Aside from this, there is no requirement that panelboards be installed vertically, just that circuit breakers not operate so that up=off and down=on. Oh, and they're no longer permitted to be installed face up. (Maybe that's coming in the 2023 NEC.)

    So this, and the similar rule for SPST switches, is just about the only place where I find verticality an issue. Now we defer to the AHJ. Is the panelboard and cabinet, or a switch box, installed at a 45 degree angle, or near one? This might be a fail. Otherwise, if it's a bit off vertical, they'd have to cite 110.12, the workmanship clause (soon to be the professionalism clause).

    As for UL standards, if they say "vertical," and don't specify degrees of slop, that's up to the NRTL listing to the standard.


  4. #4
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    Default Re: Looking for an angle

    David,

    Panelboards I was thinking about installation by humans, a how the code generically uses "horizontal" and "vertical" in describing those panelboard sections.

    Are panelboards with stab-on (versus bolt-on) breakers allowed to be installed face down? Also, how would a horizontal installation (face up, face down, sideways) affect heat dissipation? And a horizontal face down installation affect working space? Panelboards are designed for "vertical" installation and code working space is designed around such (versus face up or face down horizontal installation).

    "Vertical" should be a defined term if something other than 'yeah, anything over 45? off vertical isn't "vertical", ya know'.

    I didn't ask it as a "funny question", I asked as a serious question as that is the point your question is starting at ... and part of the ultimate answer.

    Jerry Peck
    Construction Litigation Consultant - Retired
    www.AskCodeMan.com

  5. #5
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    Default Re: Looking for an angle

    Jerry, I agree that ideally everything with legal status is defined explicitly rather than being left to judgment.

    Yes, the working space issue gets awfully interesting if a panelboard is installed face down. However, the new change forbidding face-up installation was created not because of the challenge of defining clear working space but because of a panel installed in a laundromat, where crud could land on what's normally the front, as I recall.

    Face-down installation is not ruled out. This gets especially interesting with the new 2023 requirement that clear working space shall be as flat and level as practicable.

    Careful angle measurements? Forget it. Inspectors can't carry protractors; they are not granted enough time for protracted inspections.


  6. #6
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    Default Re: Looking for an angle

    Quote Originally Posted by david shapiro View Post
    Careful angle measurements? Forget it. Inspectors can't carry protractors; they are not granted enough time for protracted inspections.
    Having done AHJ electrical inspections for over 10 years, but fortunately knot in areas where SE cable was used (a raceway with a raceway weatherhead used if the service was not underground), few inspectors I knew would actually take much time to look up at the weatherhead, not even to look at the height above the roof, the distance over the roof overhang, or conductor length over the roof overhang. Underground service laterals removed all those things from even needing to be looked at, which was good in that aspect.

    I think you are barking up the wrong tree ... the squirrel is treed up in that tree over there.

    Code cannot address stupidity. The house we bought last year here in Asheville, NC has the electrical panel at the end of the hallway past the laundry room just off the kitchen, and the working space is oversized (larger than is required at basically about 42"x42"), but ... that working space is the top landing at the stairs to downstairs - if one needed to jump back, forget about the electrical shock hazard, you are falling down a full set of stairs and the resulting injuries from hitting the bottom. Does it "meet code"? Yes, it does. Is it safe? Nope.

    Jerry Peck
    Construction Litigation Consultant - Retired
    www.AskCodeMan.com

  7. #7
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    Default Re: Looking for an angle

    David,

    Let's start back at you first paragraph about facia angles.

    The common fascia angles I've seen, expressed as a roof slope, would be: horizontal for flat/low slope roofs; 3:12; 4:12; 5:12; 6:12; 7:12; 9:12, and then less common - 12:12; 14:12; and 20:12.

    Which takes us back to 'what angle do you want to design for?' With the answer being that no designed in angle will work to eliminate what I think you are describing, and in some cases it may increase the issue.

    Could the solution be to incorporate an extended 'rubber neck bushing if x inches' to increase the weather protection qualities of the weatherhead?

    Jerry Peck
    Construction Litigation Consultant - Retired
    www.AskCodeMan.com

  8. #8
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    Default Re: Looking for an angle

    Quote Originally Posted by Jerry Peck View Post
    David,

    Let's start back at you first paragraph about facia angles.

    The common fascia angles I've seen, expressed as a roof slope, would be: horizontal for flat/low slope roofs; 3:12; 4:12; 5:12; 6:12; 7:12; 9:12, and then less common - 12:12; 14:12; and 20:12.

    Which takes us back to 'what angle do you want to design for?' With the answer being that no designed in angle will work to eliminate what I think you are describing, and in some cases it may increase the issue.

    Could the solution be to incorporate an extended 'rubber neck bushing if x inches' to increase the weather protection qualities of the weatherhead?
    Thank you, Jerry. So 3:12 is the flattest common angle for sloped roofs.

    The neat thing about standards work is that usually the STP doesn't have to prescribe a solution, just a test. It may very well be that current designs don't need to be modified one whit in order to pass a test that sprays them when held cocked. (The test: water is sprayed at them from each side at a 45 deg downward angle, after which some tissue paper tucked inside is weighed to determine how much it has absorbed.) However, because 514B doesn't offer testing with the fitting secured at an angle, the Guide Card defaulted to "vertical" and some AHJs take that as Writ, and write violations based on it.


  9. #9
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    Default Re: Looking for an angle

    Quote Originally Posted by david shapiro View Post
    However, because 514B doesn't offer testing with the fitting secured at an angle, the Guide Card defaulted to "vertical" and some AHJs take that as Writ, and write violations based on it.
    Which brings us back to that word "vertical".

    So here is another question about "vertical" which I considered bringing up before but didn't:

    Vertical in which direction?

    Most (but not all) fascia is installed "vertically", whether it is run horizontally along the bottom of a roof which slopes up from the bottom edge, or up a rake edge of the angled slope.

    Occasionally, more likely "rarely", the fascia not installed "vertically", but is installed ar a slight inward slope from the top of the fascia to bottom of the fascia. On those buildings, the rake is typically kept installed vertically, but I have seen a few with the rake also having a matching inward slope.

    Thus, is "vertical" as viewed from the front of the weatherhead, from the side of the weatherhead, or both planes?

    Installing a weatherhead on a sloped (not vertical) fascia would increase the weather protection ability of the weatherhead; however, such angled attachment may create undue stress on the mounting attachment areas of the weatherhead.

    Jerry Peck
    Construction Litigation Consultant - Retired
    www.AskCodeMan.com

  10. #10
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    Default Re: Looking for an angle

    Dagnab it, Jerry, you sound like you've looked at some of the device boxes I've installed, even in my house. Vertical they are in terms of side-to-side rotation, but cocked just a bit front to back, which occasionally took a bit of feathering at the, I suppose I might call it, leading edge. Sigh.

    In terms of weatherhead installation, I think that an inspector would be highly unlikely to fuss about it being cocked forward or back if on cable. On a raceway, if it's PVC or nylon there's some give, if not right there then in the kick or the expansion or expansion/deflection coupling. Myself, I've also been known to use washers or a bushing to bridge to an uneven mounting surface, if I've seen this as viable. Never gotten a complaint or red tag for it, so long as it wasn't an uncertain lash-up.

    The water spray test is going to have the weatherhead in the same plane as the spray heads, and it seems quite unlikely that a NRTL would use a mounting surface that was at a noticeable angle to the plane. I presume that they presently mount weatherheads in a neutral position with respect to the spray heads on either side: that meaning of "vertical." I imagine this would give the products the best chance of passing the test, and adding gratuitous impediments risks losing a manufacturer's business.

    Will anyone want to mess with this? That's what I'll investigate next--after confirming with more senior STP members that this idea has not previously been bruited.


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