When installing drop in 4X4 fixtures, what is the proper support wire gauge.

"Wire, chain or threaded rod of sufficient strength to carry the fixture."

[This message has been edited by LK (edited 03-11-2004).]

Certainly most chain you are apt to use or threaded rod (if anybody uses threaded rod for this) would carry the load. You usually use the same wire as supports the ceiling. Even so, since you support diagonal corners or all four corners (depending on local code) you can usually use something like 18ga steel tie wire if the length is not too great.

-Hal

LK:

Support of lay-in fixtures is NOT an NEC requirement, it may be local (siesmic/building/mechanical/fire.)

As to the gauge, with my EC hat on, we use the same wire that the ceiling guy uses. If it's a quantity job, I have the ceiling contractor drop 2 for me, and pay him. I find this is a 'good move', especially in a building with a high roof deck. The $$ is well worth it.

On small jobs, we get 'ceiling wire' from either Jaeger Lumber, or an Ace Hardware.

John

It depends what siesmic design category you are in. Where are you located?

Here in Utah, we are in "seismic design category D2" which means we have to install ceiling grids (and the lights attached to them) in accordance with the CISCA 3-4 Standard. If I remember right, the CISCA requires #12, but don't quote me on that part.

... Yep, Ryan,...it's #12 gauge,steel,or galvanized,...guy wire..I only know cuz I had to install troffers with that..as well as drive screws thru the casing to the T-bar grid...
AR

Attic Rat: Every time I read your profile I laugh aloud. You must be a fun guy to drink a beer with.

The reason for the gauge question, is while checking a job today, the building inspector was there, and he handed the owner a completion ticket for the ceiling, well we had temp. wire #18 holding the fixtures until the 12ga was installed. I was wondering how it passed with the 18ga., I am still continuing with the 12ga. that we always use.

Here in MA we are required by the MEC (MA Elec Code) to do the diagonal support thing with or without attachment to the grid itself.

We use the 12 AWG ceiling wire and we own all the tools a ceiling guy does, ramset on a pole, 15' tek screw drivers etc along with an open acount at a cieling supply place.

We did have an inspector refuse the 12 AWG steel wire and had us use 12 AWG Jack chain.


This is foolish as a 12 steel ceiling wire will support my weight a 12 jack chain will not come close to holding me up.

Had to re support almost 1000 fixtures, GRRRRRR!

It turned out to be an local ordnance that we could not get out of.