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#57863 10/24/05 11:41 PM
Joined: Dec 2003
Posts: 524
Member
... Shockmaster21,... you mentioned that you guys used 1/2" 8-32's in a 4" plaster ring... did you re-tap the holes?? a common plaster ring usually is threaded for 6-32 screws.. were you using "1900" 4" square boxes or 4" octagonal boxes in the ceiling??
I'm just trying to get a mental picture of your installation..
Russ


.."if it ain't fixed,don't break it...call a Licensed Electrician"
#57864 10/25/05 05:45 AM
Joined: Jan 2003
Posts: 4,391
I
Moderator
AR, A 3" round x 4" square plastering will have 8-32 holes. [Linked Image]


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#57865 10/25/05 07:49 AM
Joined: Oct 2004
Posts: 135
B
Member
I think that even today, except in the extreme, outlandish cases that the media hypes, most lawsuits are settled in a reasonable way. If using the 8-32 screws is indeed "industry standard practice", which it is, there would not be a liability issue any more so than usual. I think the foreman in this case is being a bit overzealous, but, he's the boss.

[This message has been edited by BobH (edited 10-25-2005).]

#57866 10/29/05 05:07 AM
Joined: Oct 2005
Posts: 5
S
Junior Member
Hi, all,
Thanks for your input and insight. As I thought, exploring this issue has proven to be interesting and informative. FYI, here are some comments from UL and NEMA. Sorry about the length.
=====================================
An authorized use of the UL Mark is a manufacturer’s declaration that a product was originally manufactured in accordance with the applicable requirements when it was shipped from the factory. When a UL Listed product is modified after it leaves the factory, UL has no way to determine if the product continues to comply with the safety requirements used to certify the product without investigating the modified product. UL can neither indicate that such modifications “void” the UL Mark, nor that the product continues to meet UL’s safety requirements, unless the field modifications have been specifically investigated by UL. It is the responsibility of the regulatory authority to determine the acceptability of the modification or if the modification is significant enough to require one of UL’s Field Engineering Services staff to evaluate the modified product. UL can assist the regulatory authority in making this determination.

If a party would like UL to determine if the modifications made to a UL Listed product comply with UL requirements, the appropriate Field Engineering Service can be initiated to investigate the modifications. This investigation will only be conducted after UL consults with the regulatory authority to assure that UL’s investigation addresses all areas of concern and meets all of the regulatory authority’s needs.

A field evaluation of a product can also be performed by UL for field certification of products that have not previously been evaluated or certified by UL. - From THE CODE AUTHORITY:ELECTRICAL CONNECTIONS (August - 2004) published by the Regulatory Services Department of Underwriters Laboratories, Inc.
======================================

Unless otherwise noted, the UL Mark applies to a product as it is originally manufactured—that is, as it left the factory. An exception to this is when a product has markings or instructions for such modifications (i.e., adding grounding kits for panelboards or trim rings for recessed luminaries). Only authorized accessories should be used.
Note: A modification may be intentional ( such as a repair) or accidental (such as dropping the product). UL cannot know what effect any modification (alteration, repair or accident) may have on safety, code compliance, performance on the continued UL certification of the product unless specifically evaluated by UL. - From THE CODE AUTHORITY:ELECTRICAL CONNECTIONS (July 2004) published by the Regulatory Services Department of Underwriters Laboratories, Inc.


=========================================

RE: [FEEDBACK] TECHNICAL QUESTION

Thanks for contacting NEMA with you question regarding support of luminaires.

First and foremost, the manufacturer's instructions provided with each luminaire should be read and followed as required in 110.3(B) of the NEC. If the screws that are provided with the product are critical as to length, strength, corrosion protection or material, it will state that and no substitution should be made. In addition, the manufacturer may provide components with the product that are not required by the standard or the listing for the convenience of the installer, or may substitute components that exceed the minimums required by the listing. An example might be the twist-on wire connectors supplied with many luminaires. Often these connectors are small and suitable only to connect the fixture wire to a single supply conductor. If the supply consists of several conductors, a different connector may be substituted in order to make a safe and compliant installation. In cases such as this, the manufacturer provided the connectors as a convenience.

The standard used to evaluate luminaires for use in the United States is UL 1598. The section on proper installation of a surface mounted luminaire, Section 7.2, states:
"7.2 Mounting means
7.2.1
A luminaire intended to be directly mounted to an outlet box shall be provided with two No. 8-32 machine screws if the luminaire surface containing the mounting screw holes is more than 3.2 mm (0.125 in) from the mounting surface. The length of each screw shall be at least 13 mm (0.5 in) plus the distance from the mounting surface to the luminaire surface that contains the screw holes."

Please note that this section of the standard refers to luminaires mounted directly to an outlet box, not to a pendant type luminaire. I could find no reference specifically to mounting a pendant luminaire, so I am using the above as a general requirement. Note that the section requires the manufacturer to provide two 8-32 machine screws, and that the length must be .5 inches plus the distance to cover any recess from the surface to the threaded holes in the box. It is entirely possible that the manufacturer provided longer screws to address situations where the distance from the box to the mounting surface is up to .5 inches, in which case the screw provided will still comply with the standard. If this distance is less than .5 inches, then other length screws would also comply with the standard.
In conclusion, I can offer the following:

1. The manufacturer's installation instructions must be followed. If the provided screws are required to be used in the instructions, than no substitutions should be allowed.
2. Absent any specific instructions, then substitution of a different length screw should not result in any reduction in safety for the installation, provided that:
A) The screw has full engagement of all threads into the threaded holes in the box.
B) The screw meets or exceeds the manufacturer's screw in terms of strength, diameter, and corrosion protection.

I hope this helps to address your concern. Please understand that the information provided here is general in nature and should not be used to override the manufacturer's instructions or listing requirements.



[This message has been edited by shockmaster21 (edited 10-30-2005).]

#57867 10/30/05 12:08 AM
Joined: May 2002
Posts: 68
H
Member
I'm finding many of the screws supplied with fixtures and fans these days are slightly smaller than a true 8/32 and strip out very easily.
I have started to use longer screws in fans to allow a home owner to notice it coming loose from the ceiling giving him time to get it corrected before it drops. Most of these fixtures that have these loose fitting screws are made in China and not getting reported to UL.
Are others finding the same loose screws?


Be Fair, Be Safe
Just don't be Fairly Safe
#57868 10/30/05 12:53 AM
Joined: Jul 2002
Posts: 717
M
Member
Hurk look at my post above.

#57869 10/30/05 12:05 PM
Joined: Jun 2003
Posts: 1,143
D
Member
Hurk-

You've encountered the "Chinese Standard" screw... a 6-32 winds up being 5.75-31, and a 10-24 is actually 9.87-21. [Linked Image]

And no, they're not metric. I've got a full kit of M standard and they didn't fit right either.

Of course, the makers of the screwdriver style tap tools are probably giddy over this influx... I know it's why I bought my Klein 6-in-1.

#57870 10/30/05 07:25 PM
Joined: Jul 2002
Posts: 680
W
Member
I just spent 9 days in Orlando area and was at several Disney parks

I'm truly amazed at the Electrical, Plumbing HVAC, landscaping etc involved in Disney World. I was there during Hurricane Wilma and they shut down for part of that day(monday) and opened later in the afternoon. They take in 70 million dollars a day in Orlando area parks [Linked Image]

#57871 10/30/05 09:57 PM
Joined: Oct 2005
Posts: 5
S
Junior Member
Hello Walrus,
The electrical contractor that I am presently working for cancelled work the day that Hurricane Wilma passed through. We have been working four 10 hour days (Mon-Thurs)on this particular project so we had to work the following Friday to make up for the lost day. Indeed, walt Disney World can be a facinating place to work as well as visit. I have worked at Disney World on several occasions and I am always amazed. You can find things there that an electrician could work a lifetime and never encounter. I have not personally seen any estimates as to how much money these Central Florida Theme Parks actually take in. However,I do not at all doubt your figures.

#57872 10/31/05 01:22 AM
Joined: Aug 2005
Posts: 265
S
Member
I have to laugh at the Chinese standard screws....I've used them a few times but never for a heavy fixture or fan. They are almost as good as those wire connectors that are included with fixtures.


Sixer

"Will it be cheaper if I drill the holes for you?"
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