Securing FMC

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lwilmot

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2008 NEC, Article 348.30, Exception No. 4. I'm getting hammer and looking for support or education. My contention is that FMC when being dropped from any termination point (box, transition from conduit, etc) to a luminaire or other equipment within an accessible ceiling must be secured within 12" of the termination point even if the run is less than 6'.
 
You can run up to 6' max in an accessible ceiling and the connector would be considered securing the FMC. So with a 6' run of FMC you would not have to secure within 12" of the box.
 
The 2008 Handbook notes to 348.30 exception no. 4 states "FMC fittings are not to be considered to be a means of cable support". Hence you need support after the box then count 6" to fixture.
 
Well, 320.30(D)(3) and 330.30(D)(2) for AC and MC, respectively, specifically permit the fittings to be considered means of support, so the solution is clear: make or buy AC or MC whips.

I always make sure the end with the outside wrap is the end that goes into the connector with the most tension, which would be the ceiling end in this situation, and angle connectors are better.

If you use the pre-assembled whips, keep in mind that a whip supplying more than one fixture needs full-circuit-sized conductors.
 
Every bit of light on the subject is appreciated but I'm really concerned about the securing issue and not supporting. I can't seem to let go of what I see as a requirement to secure the FMC at the transition point of another wiring method or box to the FMC regardless of the length of the FMC run. Exception 4 has this little line "from the last point where the raceway is securely fastened.....". I understand that to mean there is a requirement to first secure the FMC then if the run is 6' or less to the device no support is required. Have I really wandered off the path?
 
No there was no cange between 2005 and 2008 but in 320.30(D) and 330.30(D) it specifically states the fittings shall be permitted as a means of support. In 348.30(D) this line is omitted.
 
iwire said:
That is news to me, can you point that out in the NEC?
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Aren't the 18ga (I think) wires in the whips only suitable to feed a single fixture?

Wouldn't the wires between the J-box and all but the last fixture in line be BC conductors?

If I'm wrong, what's the whip's ampacity?
 
dcspector said:
I am hoping someone will post the nice graphics from the Mike Holt Figure 348-4 regarding section 348.30(A) Ex. 4........dunno about the 08'
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I still feel that the FMC connector can be used as the securing means. Some one posted a section 348.30(D).....that does not exist in my books. Read all the posts and then reply to this one.....:confused:
 
I think 348.30(A) Exception 3 and 4 allow you to install the fixture whip without fastening the flex between connectors.
 
dcspector said:
I still feel that the FMC connector can be used as the securing means. Some one posted a section 348.30(D).....that does not exist in my books. Read all the posts and then reply to this one.....:confused:
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I got Gypped too, my 2008 doesn't have (C) or (D)
 
iwire said:
That is news to me, can you point that out in the NEC?
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402.11 doesn't allow "fixture wires" to be used as branch circuit conductors, except where permitted elsewhere in the code.
I really don't know where it is permitted, anybody else know?
 
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lwilmot said:
Every bit of light on the subject is appreciated but I'm really concerned about the securing issue and not supporting. I can't seem to let go of what I see as a requirement to secure the FMC at the transition point of another wiring method or box to the FMC regardless of the length of the FMC run. Exception 4 has this little line "from the last point where the raceway is securely fastened.....". I understand that to mean there is a requirement to first secure the FMC then if the run is 6' or less to the device no support is required. Have I really wandered off the path?
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Iwilmot,

I understand it to mean, if running FMC for say 20 ft. and securing it as required, " from

the last point where the raceway is securely fastened " lengths not exceeding 6 ft. from

that point -----------do you agree?
 
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