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FMC Electrical Violation

250.118 maybe:

250.118 Types of Equipment Grounding Conductors.

The equipment grounding conductor run with or enclosing the circuit conductors shall be one or more or a combination of the following:
  • (1)
    A copper, aluminum, or copper-clad aluminum conductor. This conductor shall be solid or stranded; insulated, covered, or bare; and in the form of a wire or a busbar of any shape.
  • (2)
    Rigid metal conduit.
  • (3)
    Intermediate metal conduit.
  • (4)
    Electrical metallic tubing.
  • (5)
    Listed flexible metal conduit meeting all the following conditions:
    • a.
      The conduit is terminated in listed fittings.
    • b.
      The circuit conductors contained in the conduit are protected by overcurrent devices rated at 20 amperes or less.
    • c.
      The size of the conduit does not exceed metric designator 35 (trade size 11⁄4).
    • d.
      The combined length of flexible metal conduit, flexible metallic tubing, and liquidtight flexible metal conduit in the same effective ground-fault current path does not exceed 1.8 m (6 ft).
    • e.
      If used to connect equipment where flexibility is necessary to minimize the transmission of vibration from equipment or to provide flexibility for equipment that requires movement after installation, a wire-type equipment grounding conductor shall be installed.
 
To be a stickler, the camera angle provided does not prove conclusively that there is no EGC. We can only see the bottom half of the back plate of the box, so about 1/4 of the volume of the box is not visible.

So there could be a wire-type EGC inside the FMC that terminates in a lug on the top half of the back plate of the box, all hidden from view. The fact that most (all?) such boxes have a threaded hole for a grounding lug, and said threaded hole is in the upper half of the back plate, as it is not visible within the picture, makes that a bit more plausible.

If there are self-grounding 14-50 receptacles (not sure if they exist, haven't checked), then a receptacle could be installed with just the circuit conductors connected to it. If there aren't, then installing a receptacle would be trouble, unless the hypothetical hidden EGC wire goes through the hypothetical hidden lug and a pigtail is coiled up out of sight. Which isn't so plausible as a work practice, it would typically be sticking out with the circuit conductors, awaiting connection to a receptacle.

Cheers, Wayne
 
wwhitney said:
To be a stickler, the camera angle provided does not prove conclusively that there is no EGC.
Click to expand...
Stickler? Yes, for sure. Don't look for things you can't see. That is never the point. That is like me taking a picture of a window and asking a question about the roof that is not in the picture. Makes no sense.
 
ICE said:
Prudence requires that the date be ascertained to determine if the neutral was possibly used as an equipment ground.
Click to expand...
Not relevant. They moved the location of the range, and installed new conduit for the extension and a new JB. They could have continued with EMT but were lazy so now they need to pull an EGC.
 
If the neutral was a legal EGC for the range …. Would a jumper between boxes and continued use of the neutral as an EGC for the range be legal?
 
ICE said:
If the neutral was a legal EGC for the range …. Would a jumper between boxes and continued use of the neutral as an EGC for the range be legal?
Click to expand...
No. This isn't about a neutral. This is about a metal box and raceway equipment grounding. We are past the service disconnect so the grounded conductor and EGC must be separated.
 
Now that the excitement has died down, I have a question. Granted, EMT can be used as a EGC but how often do you encounter that?

For me it‘s just about never. One loose fitting and whadaya got? How about thirty year old conduit…any rotten spots?
 
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