2011 MC Cable support exception needed

[Rockyd]

Supporting cable within a foot of the box is okay for plugs, and they gave an exception to lights in an accesible ceiling, but NOTHING for motors or other large equipment. I believe there should be a three foot exception where motion and flexibility are required (as in 350.30(A) ex 2) LFMC except make the verbage apply to MC. Perhaps longer for larger (like 3-350's with a ground).

If it's about the style of connector, I could accept that (we use TMC and TMCX style fittings on HL MC) but it is unreasonable to be within a foot of a peckerhead of a motor, or dropping out of a cable tray at less than three foot above an MCC or Swithgear.

Need to work over the verbage and send it off to code making panel #7 for the next cycle in an effort to better our industry.

Anyone have experience in writing proposals? Am I missing any intent in 330.30(D) last sentence - "Type MC cable fittings shall be permitted as a means of support"?

It maybe a can of worms, but it needs to be kicked over, and fixxed. Where I currently work, jumps through all kinds of hoops to satisfy this one foot rule ( I think it is grossly miss-interpeted) so looking for some honest opinions.

 

[POWER_PIG]

330.30(b)

330.30(b)

The way I read art.330.30(B)
MC larger than 10awg will be secured no less than 6' away from termination.
Maybe the smaller MC doesn't hold up to continuous movement?. It does snap pretty easy, you must admit. Just my opinion.

 

[mdshunk]

I don't see a need for an exception for motors. Certainly a foot is enough to handle vibrations. The actual mechanical execution of the support structure is I'm sure what frustrates you, but I think it is work that needs done.

 

[iwire]

Use FMC or LFMC and you can go 3' without support.

 

[infinity]

Use FMC or LFMC and you can go 3' without support.

I agree with Bob. IMO a foot is too close for most motor installations but you do have other options.