connection of lighting

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gmayeux

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i am connecting 2x4 flourscent lighting in a suspended ceiling based on the NEC is daisy chain connection of lighting permissiable,and if using MC cable with ground can the whips be longer than 6'
 
Yes. The fixtures are being used as outlet boxes, not raceways.

(As long as the conductors the whole way are the 12 AWG MC cable for a 20A circuit, then they are protected.)

See 410.31 and 410.32 for more.
 
Yes it is allowed by the NEC. I see it on a lot of jobs. Check the specifications since many engineers frown on this installation.

Chicago codes might be different.
 
When wiring in this manner, is it required to support within 12" of j-box and

every 4.5ft. after that. I know if droping from a box it can remain unsupported

for 6', used as a fixture whip.
 
georgestolz said:
Yes. The fixtures are being used as outlet boxes, not raceways.

(As long as the conductors the whole way are the 12 AWG MC cable for a 20A circuit, then they are protected.)
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But a 6-foot #14 THHN whip, from a single fixture, can tap a 20A #12 fluorescent lighting circuit?
 
iwire said:
No.
THHN is not listed in 402 as fixture wire, check 402.3 and T402.3
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Thanks Bob. I agree 240.5 does not apply.

I believe the tap rules for a single florescent whip comes from other sections:
240.21(A), 210.19(A)(4) Ex.1 "(b) A fixture having tap conductors as provided in 410.67"

Where "A fixture" seems to apply the language from 410.67(C) to any fixture, not just incandescents or cans. The primary concern in 410.67(A)&(B) are proper insulation class for the temperature encountered, and fluorescent ballast are thermally protected, 410.73, providing for the 90c THHN tap, #14 whip on 20A circuits.
 
410.67(C) calls it a luminair, AKA "The ballast of a fluorescent luminaire (fixture)" in 410.73 (E)(1). Luminair is defined as, "lamps and ballast (where applicable)."
 
ramsy said:
410.67(C) calls it a luminair, AKA "The ballast of a fluorescent luminaire (fixture)" in 410.73 (E)(1). Luminair is defined as, "lamps and ballast (where applicable)."
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410.67 appears below the heading "XI. Special Provisions for Flush and Recessed Luminaires".

410.64 specifically explains that recessed fixtures must comply with 410.65 through 410.72.
 
Yes, I see those section dividers do not strengthen my argument for general application of NEC 410.67 to all luminaries. Probably not a great idea to test inspectors with #14 taps on 20A circuits.

However, Osha Stallcup illustrates NEC 410.67(C) to describe a fluorescent fixture tap, in a suspended ceiling.
http://books.google.com/books?id=ex...GZsd&sig=JNCIR37E9GlWBPVLTBiMaA0YNrk#PPA78,M1

Osha Stallcup's Electrical Construction Regulations shows NEC 410.67(C) in its figure 11-97, with uses permitted for fixture wire, among the OSHA references.
 
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Decided to check with my local building department in Fullerton, Ca.

The plans engineer is not familiar with reduced wire sizes for taps, not even recessed cans. He points out NEC 410.67 does not refer to any wire sizes, reduced or otherwise, and suggests the purpose of that section is daisy-chaining between fixtures only, or sub-fixtures without ballasts.

The impression I was left with, was that my #14 luminary tap coming from a 20A circuit could be red tagged, and stay that way, no matter how blue in the face I got from thumping the code book. Looks like, I'll need to replace my 20A lighting breaker with a 15A.
 
tallguy said:
410.67 appears below the heading "XI. Special Provisions for Flush and Recessed Luminaires".

410.64 specifically explains that recessed fixtures must comply with 410.65 through 410.72.
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410.64 says recessed but the titles of part 11 + 12 state that they also cover flush mounted lights. . 410.65(C) is the part that is exclusively applicable to recessed only.

David
 
em fixtures in sw gear room

em fixtures in sw gear room

Is it a code requirement to have em lighting in sw gear rooms?
 
dnem said:
410.64 says recessed but the titles of part 11 + 12 state that they also cover flush mounted lights. . 410.65(C) is the part that is exclusively applicable to recessed only.

David
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I'm pretty sure that "flush" in this case is synonymous with "recessed". One can't make a light flush unless it's body/can is recessed. 410.64 through 410.72 does not differentiate between "flush" and "recessed" and as a matter of fact the word "flush" doesn't appear at all AFAIK -- it's only in the title of the section.

410.65(C) applies exclusively to incandescent (as does 410.70)...
 
tallguy said:
I'm pretty sure that "flush" in this case is synonymous with "recessed". One can't make a light flush unless it's body/can is recessed. 410.64 through 410.72 does not differentiate between "flush" and "recessed" and as a matter of fact the word "flush" doesn't appear at all AFAIK -- it's only in the title of the section.

410.65(C) applies exclusively to incandescent (as does 410.70)...
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Recessed
Surface
Flush

Of the 3, the word "flush" should never be used because it's always unclear what is meant. . "Recessed" is obvious. . "Surface" is easy enough to understand. . But is "flush", flush finish or flush mount ? . Flush finish is the same thing as recessed, but flush mounted is the same thing as surface mounted.

As far as 410 parts 11 + 12 are concerned, if the word "flush" here meant flush finish, there would be no need to list flush finish and recessed. . Because they're both listed side by side, that tells me it should be applied to flush mounted [surface] and recessed.

David
 
dnem said:
Recessed
Surface
Flush

Of the 3, the word "flush" should never be used because it's always unclear what is meant. . "Recessed" is obvious. . "Surface" is easy enough to understand. . But is "flush", flush finish or flush mount ? . Flush finish is the same thing as recessed, but flush mounted is the same thing as surface mounted.

As far as 410 parts 11 + 12 are concerned, if the word "flush" here meant flush finish, there would be no need to list flush finish and recessed. . Because they're both listed side by side, that tells me it should be applied to flush mounted [surface] and recessed.

David
Click to expand...

What you are saying makes sense... it's a confusing section IMO though as it does not draw a clear distinction between the requirements for each type (recessed and flush mount).
 
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