EMT Support

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EMT Support

  • Yes. Strap within 3 ft

    Votes: 25 58.1%

  • No, You can strap within 10 ft.

    Votes: 18 41.9%
  • Total voters
    43
  • Poll closed .
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augie47

augie47

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Tennessee
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State Electrical Inspector (Retired)
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
 
E

earlejohnson

Member
Location
ga.
augie47 said:
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
Click to expand...

No I would say start your straping 10 ft from slab
 
Little Bill

Little Bill

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Location
Tennessee NEC:2017
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Semi-Retired Electrician
augie47 said:
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
Click to expand...

Augie,
I suspect this is another one of your questions that you already know the answer to, but I'll give you what I see about this. I know that the handbook, other than the actual code, is just someone's commentary. In the 2005 handbook, the commentary/exhibit following 358.30 shows a run of EMT with couplings. The strapping starts 3' from a junction box then goes in 10' sections including couplings, before another strap. Then continues in 10' sections with couplings to the termination point (junction box). You are probably asking because of the transition from 3/4" RMC. I would say if the transition was tight (proper adapter) that you wouldn't have to strap it within 3' of the transition.
Ok, that's my opinion, now I'll brace for correction.
 
C

Cow

Senior Member
Location
Eastern Oregon
Occupation
Electrician
augie47 said:
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
Click to expand...

I sure hope not, I don't strap 'em.
 
Dennis Alwon

Dennis Alwon

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Location
Chapel Hill, NC
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Retired Electrical Contractor
A coupling is not a termination.

348-13.gif
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
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retired electrician
Based on the code wording, I see the connection between the two types of raceways as a "termination" for each raceway. One raceway ends and the other starts. With couplings in the same type of raceway, the raceway does not have a termination.
 
augie47

augie47

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Location
Tennessee
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State Electrical Inspector (Retired)
don_resqcapt19 said:
Based on the code wording, I see the connection between the two types of raceways as a "termination" for each raceway. One raceway ends and the other starts. With couplings in the same type of raceway, the raceway does not have a termination.
Click to expand...

That's what makes it intertesting. ;)
 
Dennis Alwon

Dennis Alwon

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Location
Chapel Hill, NC
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Retired Electrical Contractor
How can a coupling be a termination. It joins two pieces together. Is a 100 foot run of emt considered 10 raceways or 1 raceway?
 
iwire

iwire

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Location
Massachusetts
I think the confusion stems from the fact that code used to require a support within 3' of a fitting and couplings are fittings so going back a few or more code cycles you had to have a support near couplings.

Now we are not required to, although my personal policy is to put supports near couplings.
 
iwire

iwire

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Location
Massachusetts
don_resqcapt19 said:
Based on the code wording, I see the connection between the two types of raceways as a "termination" for each raceway. One raceway ends and the other starts. With couplings in the same type of raceway, the raceway does not have a termination.
Click to expand...

Interesting, the EMT does terminate.
 
qcroanoke

qcroanoke

Sometimes I don't know if I'm the boxer or the bag
Location
Roanoke, VA.
Occupation
Sorta retired........
augie47 said:
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
Click to expand...

How is it transitioning to EMT?
With a fitting listed for the purpose or a ridgid coupling screwed onto the ridgid with an EMT connector screwed into the other end? :0)
But no a coupling is not considered a termination point. How could it be when the tubing is continuing on?
Like iwire I would strap it way closer than 10 feet away from the coupling.
 
al hildenbrand

al hildenbrand

Senior Member
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
augie47 said:
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
Click to expand...

don_resqcapt19 said:
Based on the code wording, I see the connection between the two types of raceways as a "termination" for each raceway. One raceway ends and the other starts. With couplings in the same type of raceway, the raceway does not have a termination.
Click to expand...
I think it becomes tricky to substitute the Article 100 Definitions defined term "raceway" for "tubing". Raceway includes items that I would not consider to be tubing, . . . busway, for instance.

"Tubing" is used 199 times in the 2008 NEC. It is not defined, and includes things that are not raceways, such as neon tubing, skeleton tubing, or insulated copper tubing of pneumatically operated fire detectors.

Augie's citation of 358.30(A), above, uses the unmodified word "tubing". It doesn't say "type of tubing". In fact, I believe "tubing termination" is a two word term.

In Augie's OP question, the 3/4" Rigid 90, while not specified as RMC or PVC, is still readily understood to be "tubing", in my opinion.

A "go-from" coupling maintains the tubing alignment for the purpose of pulling in conductors without the need for access to the conductors present, or future.

A "go-from" coupling, while connecting different tubing (say a 1/2" EMT to a 3/4" EMT, or 3/4" PVC to 3/4" EMT) merely couples the tubing, it does not terminate the tubing.

The term "tubing termination" is in a list of items that introduce access to the conductors. A coupling that joins different types of tubing, does not terminate the tubing, rather, the coupling joins tubing.
 
S

Strife

Senior Member
How far from the slab is the transition?
Usually my GRC stub would be 1' or so, so in that case it'd be within 3' of the transition.

augie47 said:
Art 358 States:
"(A) Securely Fastened. EMT shall be securely fastened in place at least every 3 m (10 ft). In addition, each EMT run between termination points shall be securely fastened within 900 mm (3 ft) of each outlet box, junction box, device box, cabinet, conduit body, or other tubing termination."

Is a coupling considered a "tubing termination" ? Specifically, if one has a
3/4 rigid 90 stubbed from a slab then transitioned to EMT, does the EMT have to be strapped with 3 ft of the transition ?
Click to expand...
 
don_resqcapt19

don_resqcapt19

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Staff member
Location
Illinois
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retired electrician
When you change from conduit to tubing, I think it is clear that the conduit and tubing both end or start at that point. That makes the connection point a termination of both the conduit and the tubing. A support is required for the tubing within in 3' of its termination and for the conduit within 3' of its termination.
(note this is my opinion of what the code rule requires and not how I would make the installation).
The new wording in the 2011 code for Exception #2 to 350.30(A) is going to trigger the same type of discussion for the support of LFMC.
 
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