Wiring lights in a drop ceiling


I plan to install several lights in a drop ceiling.
Question: Do I need to run MC cable to each light from a covered box centrally located in the room in a star topology, or can I run one MC cable to the box attached to the first light and to the next and next in a daisy chain configuration ?
Thanks
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Never having worked with it and just glancing at a page or two that google found for me, I would say it is considered "conduit" and can be run either way with proper support.
Allowing it to rest on top of the dropped ceiling grid would be a no-no.
Attached to the structure above I can't think of any reason why you can't daisy chain as long as you have the proper connectors at each box.
Colbyt
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On Sat, 10 Apr 2010 18:08:00 -0400, "Colbyt"

Using BX (flexible armoured cable) it does not need to be supported above the drop ceiling. It is done that way all the time in commercial applications
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On 4/10/2010 6:23 PM snipped-for-privacy@snyder.on.ca spake thus:

>>

Except you don't need BX; the MC that the OP suggested would be perfect.
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On Sun, 11 Apr 2010 21:32:23 -0700, David Nebenzahl

Both have to be supported within 6 feet of the luminaire
BTW nobody really calls it BX these days. That was a trade name for an obsolete predecessor of AC cable (no bonding strip). Most electricians since the Eisenhower administration either talk about MC or AC. They have an actual reference in the NEC.
As I said a long time ago. in a dwelling, he can just use NM-b (Romex or one of the other brands). No hacksaws or special cutter required.
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You can wire them daisy chained to properly sized outlet boxes, or recessed fixtures that have junction boxes rated for feed through. I'm assuming this is a commercial application, which is why you're using MC
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No, its not commercial, just wanted to be cautious. How can I tell if the fixtures that have boxes attached are rated for feed-through ?
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No, its not commercial, just wanted to be cautious. How can I tell if the fixtures that have boxes attached are rated for feed-through ?
It will say so, either on the junction box itself, or in the literature that comes with it
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.
Fixture: Halo H7ICT Attached junction box reads: Maximum of 8 No 12 AWG through branch conductors.
So I assume this means max wire count of 8 in the box. Would 14 AWG be acceptable ?
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wrote:

It can handle up to 8 #12s, and #14 is smaller, so yes, unless the total circuit load is over 12 amps (80% of 15 amp circuit) #14 should be fine. (about 1450 watts)
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On 4/10/2010 7:15 PM, sid wrote:

Yes.
Must use 15 amp breaker only, though. How many fixtures and what wattage are you planning on using? Is this a dedicated circuit?
Test cut the MC cable a few times to set your blade depth before trusting that you won't nick the conductors inside.
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How do you set the blade depth on a hacksaw?
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On 4/11/2010 6:51 AM, RBM wrote:

You don't. You don't use a hacksaw for MC cable terminations, either.
This is the proper tool:
http://preview.tinyurl.com/y94zuvq
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That's very funny. For nearly a hundred years before "the proper tool" was invented, we electricians have been using hacksaws to properly cut steel and aluminum cable without any damage to the conductors, but suddenly it's not a proper method anymore.
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Fixture: Halo H7ICT Attached junction box reads: Maximum of 8 No 12 AWG through branch conductors.
So I assume this means max wire count of 8 in the box. Would 14 AWG be acceptable ?
The junction box will hold more #14 conductors than#12. If you use the MC, make sure you have MC connectors and not BX(AC) connectors
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wrote:

This is one of those things that may get a local spin but the NEC does allow you to use a 4.5 foot whip of Romex in a dwelling to serve lights in a dropped ceiling. (not in commercial or multifamily) You can certainly use MC but it is probably not necessary. They can be daisy chained as long as you support the cable (romex or MC) every 4.5 feet. or 6 feet for MC
334.30(B) Unsupported Cables. Nonmetallic-sheathed cable shall be permitted to be unsupported where the cable: (1)     Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable. (2)     Is not more than 1.4 m (41/2 ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of connection are within an accessible ceiling.
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sid wrote:

I've seen both ways. I don't think code cares, other than a star topology may run you into box-crowding and maxed-out wirenut problems, if you have lots of lights. I'd do it whichever way used the least amount of cable and was most painless to pull, and also wouldn't be a pita for any later work in the ceiling.
But then again, I am not an electrician.
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wrote:

Daisy chaining is common practice.
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On 4/10/2010 4:10 PM, sid wrote:

You may use either method. It might be easier to have two junction boxes that branch to multiple fixtures.
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