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#57497 - 10/16/05 06:36 AM Hanging Metal Halide fixtures
coachman Offline
Registered: 12/06/01
Posts: 15
Loc: Cherry Hill, NJ, USA
I am installing 400watt metal halide fixtures in a wharehouse with concrete ceilings & concrete beams. What type anchor for the boxes should I be using?
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#57498 - 10/16/05 07:09 AM Re: Hanging Metal Halide fixtures
earlydean Offline
Registered: 12/22/03
Posts: 751
Loc: Griswold, CT, USA
I have had success in the past with lead anchors. They require a set-tool, but they do get a good grip on the inside of the concrete hole.
Another option is epoxy.
#57499 - 10/16/05 07:51 AM Re: Hanging Metal Halide fixtures
Cow Offline
Registered: 07/01/05
Posts: 33
Loc: Hermiston, OR
1/4 inch wedge anchors(red heads) would hold well also, although lead anchors are quicker and easier to install.
#57500 - 10/16/05 08:34 AM Re: Hanging Metal Halide fixtures
Tiger Offline
Registered: 05/04/05
Posts: 706
Loc: Crystal Lake, IL USA
Just a note that these fixtures have some hazards. I'm considering alternate fixtures on my commercial projects.

#57501 - 10/16/05 08:46 AM Re: Hanging Metal Halide fixtures
Redsy Offline
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA

Keep in mind that some concrete ceilings consist of pre-cast slabs, which often have hollow portions.
If thats the case, you may need toggles, or t-anchors.
#57502 - 10/16/05 03:02 PM Re: Hanging Metal Halide fixtures
sierra electrician Offline
Registered: 02/12/05
Posts: 219
Loc: North Fork, CA USA
Lead anchors and wedge's work good for supporting a box. I hope your not planning to hang the fixture from that box, if so epoxey might be better. I has a much higher pull rateing.

#57503 - 10/16/05 06:56 PM Re: Hanging Metal Halide fixtures
Jps1006 Offline
Registered: 01/22/04
Posts: 615
Loc: Northern IL
I prefer the wedge because the load will continue to "wedge" or put pressure on the frictional surfaces. I have had inspectors in the past disallow lead as support means in this type of application because in fire they would melt at a lower temp and become one more hazard for the firemen.
#57504 - 10/16/05 07:40 PM Re: Hanging Metal Halide fixtures
dmattox Offline
Registered: 10/20/04
Posts: 265
Loc: Anaheim, CA
Did a google search and I found this site that compares concrete anchors. The only 2 that are rated for heavy duty are:

I use the later all the time. Can be a bit of a nightmare if you screw them. But, they hold really well.

Never tried the first one, it looks kinda interesting though.

Look at the ratings though, 900lbs+ using the 1/4". Plenty strong for a fixture as long as the concrete is in good shape.

[This message has been edited by dmattox (edited 10-16-2005).]
#57505 - 10/16/05 07:59 PM Re: Hanging Metal Halide fixtures
electure Offline

Registered: 12/24/00
Posts: 4259
Loc: Fullerton, CA USA
Be sure to find out beforehand if you've got a "post-tension" concrete structure before selecting any anchors.
Post-tension decks can only have anchors that are very shallow without x-raying the deck and getting a structural engineer's OK.

If that's the case, Hilti makes some 3/8" slugs that will do the trick.
#57506 - 10/17/05 05:20 AM Re: Hanging Metal Halide fixtures
e57 Offline
Registered: 05/27/03
Posts: 2876
Loc: S.F.,CA USA
Ditto on knowing the contruction of the cieling. I was in a building where the sprinkler installer hit a post tension cable, and sent it half way out the side of the building. They had to have re-engineering of the floor loading, after X-raying most of the floor.

Hilti makes a really expensive heavy duty under-cutting anchor that is great for this, but check around, 'cause Hilti has some licensed under other names that are less expensive, and the same product. for instance Toggler (TM) is the same as the Hilti toggle bolt, but 3X as much.

And if you use epoxy, blow out the hole, or you're just sticking to dust.
Mark Heller
"Well - I oughta....." -Jackie Gleason
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