What does 300.18 exception mean?

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charlie O

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This is my first time posting on here guys, so please forgive me if I happen to post this in the wrong place, or just plain wrong...:?

Recently I was faced with a installation that involved a 3/4" EMT conduit connecting a outlet in a office to a juction box in the drop ceiling. The conduit is installed in a concrete filled non-moisture subjected block wall that separates offices inside a wherehouse. The conduit was cut too close to wall and right at the the pipes bending radius making it impossible to put a EMT connector on as to attach it to the 4 square junction box. Since the wall is block, and the EMT conduit is set in concrete, the only option I could see to do, minus cutting & jack hammering concrete and making a huge mess, was to install a hammer-on plastic bushing and put the 4 square box over the conduit, anchoring it to the wall. Therefore, the EMT raceway is connected at the outlet box with a fitting, but not at the 4 square juction box in the ceiling. Conduit is secured in concrete, and junction box is secured to wall, so no movement possible between the two. The conductors are in the junction box and are protected entering the conduit by the plastic bushing, and all grounding connections at the outlet box, and juction box are attached providing a continuous ground for the system. The integrity of the electrical system wasn't compromised as far as I can see.

Question, reading 300.18 on raceway installations, I want to know what your opinion is about the exception which states, "Short sections of raceways used to contain conductors or cable assemblies for protection from physical damage shall not be required to be installed complete between outlet, junction, or splicing points."
Also 300.12 Exception No. 1
I 'm referencing this because of 358.30 which states, "EMT shall be installed as a complete system in accordance with 300.18..."

Does this cover the installation above? Any other comments welcome.
Thank You
Charlie O
 
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i don't feel the exception covers that install however I would not reject it.
I don't personally see a big difference in that and stubbing up into a open bottom switchboard,
 
If the emt was used a race way and a cable assembly was ran in it would it be acceptable ?
If the emt ran onto an enclosure with a removed back cover is that the same thing Mr.augie?
 
electricalist said:
If the emt was used a race way and a cable assembly was ran in it would it be acceptable ?
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Unless it was a cable type permitted for raceway wiring method, such as Type TC, I'd say installing cable in that run would be less acceptable than using single conductors.

If the emt ran onto an enclosure with a removed back cover is that the same thing...?
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An enclosure with removed back cover would likely be non-compliant. Not the same a a 4sq with EMT stubbed into a KO. Now if the back cover was not removed, enclosure secured to wall, and EMT stubbed into it... then you'd have the same scenario.

FWIW, 300.18 says run must be complete, but it establishes no criteria for determining a complete run. That leaves it open to AHJ interpretation.
 
electricalist said:
It's early gimme a minute.
I'm only looking for the op a sollution. In commercial remodels I've seen lots of mc ran down emt to re feed .
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I've seen a lot of things done that weren't to Code... and I don't imagine that's going to stop any time soon... :happyno:
 
mwm1752 said:
330.10(7)
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Yeah, that one's a bit of a puzzler to me... but there it is in black and white. :blink:

is there a meaning for the $
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If you are referring to my username, it means exactly what it means... but it is intentionally a play on a person's own disposition, i.e. if you read it as implying something other than what it means, that is on you.
 
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