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Secured within 12" for MC cable NEC 330.30(B)

Discussion in 'Electrical Codes' started by jar546, Sep 8, 2018.

  1. jar546

    jar546 *****istrator

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    So, although this job is not ready for inspection, the potential issue here with this MC installation is that on the right side, the MC clamp is 16" away from the box/fitting.

    Who out there would fail this installation for having 1 strap more than 12" away?

    IMG_1094.jpg
     
  2. north star

    north star Sawhorse

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    @ ~ @

    By not enforcing the adopted requirement of the NEC, and specifically
    Article 330.30(B), ...then a precedent would then be set........What
    about the next time, and THERE WILL BE a next time, ...when the distance

    is a little bit farther, and the next time when the distance is still even
    farther away ?.......How many of us have heard the statement "Well you

    didn't make me do it on the last job, why are you making me do it now" ?

    Anyone who is a regular visitor or member on this Forum sees the direct
    results of what happens when the various adopted Codes & Standards
    are not enforced [ i.e. - please refer to the various pictures and
    applications that **ICE** has ].


    IMO, ...as an Inspector the non-compliant condition must be enforced to
    the Code [ read Article ] as adopted by the jurisdiction.


    @ ~ @
     
  3. jar546

    jar546 *****istrator

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    The alternative to this would be taking the MC cable on the right, bringing it back to the left side just to secure it then looping it back causing undue stress on the connection point and wasting cable. The cable tie in the middle is acting as a support.

    What if I told you this installation was under the 2017 NEC and that the cable ties were UL Type 21S? Would that change your opinion?
     
  4. ICE

    ICE Sawhorse

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    Will the ceiling be accessible?

    330.30(D)(2)
     
    #4 ICE, Sep 9, 2018
    Last edited: Sep 9, 2018
  5. RJJ

    RJJ Platinum Member

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    My response to both OP post would be that one the tie secures them both. It appears to be about 6" out of the box. Therefore, the right side would be ok. On this install I would use a little "common sense" and not fail it. Seeing this I would look closely at the other devises, to make sure they are done correctly. It appears to be on 24" centers and some time the can does not line up with the desired center wanted from below.
    Also keep in section 330.24 not to create stress on the bend. I believe the installer has meet the burden of the code.
     
    jar546 likes this.
  6. jar546

    jar546 *****istrator

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    Yes
     
  7. ICE

    ICE Sawhorse

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    330.30 Securing and Supporting.

    (D) Unsupported Cables. Type MC cable shall be permitted to be unsupported where the cable:

    (2) Is not more than 1.8 m (6 ft) in length from the last point of cable support to the point of connection to luminaires or other electrical equipment and the cable and point of connection are within an accessible ceiling. For the purpose of this section, Type MC cable fittings shall be permitted as a means of cable support.
     
  8. fatboy

    fatboy Administrator

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    My reaction was that with the cables being attached to one another, appears to immobilize them within the 12". JMHO
     
  9. ICE

    ICE Sawhorse

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  10. ICE

    ICE Sawhorse

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    Is it 12" as the pig flies or is it 12" of actual MC cable. Neither cable is 12" or less in actual cable and if it is as the pig flies then the cables could be infinitely long. So one cable is attached to another, however, the point is moot given the Code.
     
  11. Pcinspector1

    Pcinspector1 Platinum Member

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    I don't see a problem with this install, help me understand what the code is trying to achieve.

    If the light fixture was to drop during a fire or a shake, would it drop too far or would this install still provide the safety needed?

    As far as 330.24 bending radius, it appears to be in compliance.

    Would you measure the 12-inches of material or from the distance from the wood framing fastener to the light fixture box?
     
  12. Pcinspector1

    Pcinspector1 Platinum Member

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    Wouldn't the MC require the metallic type approved 21's ties?

    Have to be a wrapper laying on the floor for verification, cuz I can't tell one tie from another.
     
  13. RJJ

    RJJ Platinum Member

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    PCinspector1: The OP was dealing with the 12" rule for fasting. The install meets the NEC requirements. By use of the tie the installer has meet the requirement.
     
    JCraver, fatboy and Pcinspector1 like this.
  14. jar546

    jar546 *****istrator

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    Basically this is an accessible attic space and these are luminaires so I could put a 6' fixture whip on this unsecure and it meets the code. The 12" rule does not even apply for this application. I was trying to see what some of the opinions were out there to drum up some conversation.
     
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  15. RJJ

    RJJ Platinum Member

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    Well I 'll be: Never gave it a though in regards to the 6' rule for a whip. I see hundreds of these installations every week with the 6' or less whip being used. A very good and tricky question!!!
     
    fatboy likes this.
  16. fatboy

    fatboy Administrator

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    Yup...messing with us, made us over-think it.
     
  17. Rick18071

    Rick18071 Sawhorse

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    I don't think a wire tie from a MC cable to another MC cable can be used for supporting:

    300.11 (C) Cables not used as a means of support. Cable wiring methods shall not be used as a means of support for other cables, raceways, or non electrical equipment.

    But if this is a whip it's ok for the first 6'.but not elsewhere.
     
  18. RJJ

    RJJ Platinum Member

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    Rick: Very good point. Installers like using wire ties. So would that use of a tie even to create a nice entrance be a violation. On the surface I think it would be or could be! ????
     
  19. jar546

    jar546 *****istrator

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    Yes, "cable wiring methods" not "cable wiring"
     
  20. ICE

    ICE Sawhorse

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    It is difficult to say for sure but the way the trusses are bearing seems odd.
     

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