Short Radius Elbows not allowed to be installed in the middle of a conduit run

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Electrical User

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Trying to install a 3/4" RMC conduit from an existing stub up to an existing jbox which requires the installation of an elbow. This is located in a C1D1 Group D location (inside a gasoline dispenser). Existing 3/4" RMC conduit is stubbed up. Per 501.15(A)(4), the first fitting to be installed to the existing stub-up will be a seal-off (25%fill). Installing (1) cable with .42in OD once the conduit run is complete. Due to an overhead obstruction, a 3/4" RMC elbow compliant with Chapter 9 Table 2 radius is not possible. Additionally, there is not enough vertical clearance to install a close nipple followed by a C1D1 pulling elbow (the elbow will fit, there is not enough room to install/remove the cap due to being threaded). It appears the only viable option is using a short radius elbow such as an Appleton ELMF90-75. However, emailing the manufacturer of the short radius elbow, they state "short radius elbows are only for use right at the box or enclosure and cannot be used in the middle of a conduit run (jbox is approx. 12-14" away from stub up location)."
A short radius elbow (no removable cover) - seems very hard to pull through in the middle of a run. However, I am looking for a code section to verify the manufacturers comments that short radius elbows are only for use at the box or enclosure.
 
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hbiss said:
www.zoro.com

Appleton Electric 90Deg M and F Elbow, HazLoc, CF Alum, 3/4In ELMF90-75-A | Zoro

Order Appleton Electric 90Deg M and F Elbow, HazLoc, CF Alum, 3/4In, ELMF90-75-A at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.
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Certainly would not want to use that in the middle of a run!

-Hal
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Agreed it is not ideal - but still looking for a code section that prohibits the use of this mid-run or alternatively a code section that states it has to be used as a terminating connection.
 
don_resqcapt19

don_resqcapt19

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wwhitney said:
300.18(A) second sentence, same as other right angle fittings used as the "terminating connection at the equipment"?

Cheers, Wayne
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Not seeing how that permits the fitting in this thread. It may be the intend, but the language is not even close. The other right angle fittings are for flexible wiring methods.
 
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wwhitney

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don_resqcapt19 said:
Not seeing how that permits the fitting in this thread. It may be the intend, but the language is not even close. The other right angle fittings are for flexible wiring methods.
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For reference, the second sentence of 300.18(A) is (2017 NEC):

"Where required to facilitate the installation of utilization equipment, the raceway shall be permitted to be initially installed without a terminating connection at the equipment."

I see nothing in the language that differentiates between flexible and rigid raceways. Seems like it's carte blanche to leave out the last fitting at the equipment, pull wires, then slide the last fitting over the wires and connect the fitting to the raceway and the equipment.

Cheers, Wayne
 
tortuga

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We use them sometimes to 90 into the top of a basement panel, never in the middle of a run.
Its like a flex 90 for rigid.
 
don_resqcapt19

don_resqcapt19

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wwhitney said:
For reference, the second sentence of 300.18(A) is (2017 NEC):

"Where required to facilitate the installation of utilization equipment, the raceway shall be permitted to be initially installed without a terminating connection at the equipment."

I see nothing in the language that differentiates between flexible and rigid raceways. Seems like it's carte blanche to leave out the last fitting at the equipment, pull wires, then slide the last fitting over the wires and connect the fitting to the raceway and the equipment.

Cheers, Wayne
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I am looking for something that says they can be used? What are they listed as? The Crouse Hinds catalog shows them listed under UL 1203, but I only see 1203 covering exposionproof capped elbows.
 
don_resqcapt19

don_resqcapt19

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They are listed under 1203 and the UL Guide Information for "Conduit Fittings for Use in Hazardous Locations (EBNV)" says this
Conduit elbows and short-radius capped elbows are intended for use where it is desirable to have a 90-degree bend and where wires may be guided when being pulled through the conduit line.
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I think that is the closest I will find that says the EL must be used at the equipment, but still doesn't exactly say that.

​

 
rbalex

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I'm sorry that I’m coming late for the debate.

The question is irrelevant to hazardous locations except that the specific fitting you have cited is indeed listed for Class I, Groups A, B, C, D; Class II, Groups E, F, G; and Class III. Of course, this does not mean it has universal installation privileges.

Ultimately, the Code answer is derived from Section 110.3. Wherein the “answer” may not be in the NEC itself but in the listing or other product standards, including manufacturer instructions.

I would return to the manufacturer and ask if they have specific instructions for using this device.
 
synchro

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Is there enough surrounding clearance to first screw that short radius elbow into a type-C condulet, and then put that assembly onto the short nipple ? You'd have to swing the assembly around to screw it onto the short nipple, and so you'd need to have sufficient clearance horizontally. The cover of the type-C would be facing downward. If this could be done, then you'd have at least some access to help get the cable through the short radius elbow.

Like rambojoe mentioned, a picture of the area where the work is to be done would be helpful.
 
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rambojoe said:
I meant... a picture of the job...
I assumed you were looking for a altrrnative...
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This sketch shows the clearance above the existing stub. Not able to provide pics.
synchro said:
Is there enough surrounding clearance to first screw that short radius elbow into a type-C condulet, and then put that assembly onto the short nipple ?
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The first fitting needs to be a seal off and can't be a type-C condulet per 501.15(A)(4). A typical type-C condulet (Form 7 & 8) is C1D2 rated and is not allowed. We are in a C1D1 Group D location which would require an "EKC" conduit body or similar but still not allowed to be the first fitting.
rbalex said:
I would return to the manufacturer and ask if they have specific instructions for using this device.
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Thanks. The original post indicates the manufacturer stating, "short radius elbows are only for use right at the box or enclosure and cannot be used in the middle of a conduit run" which I have in writing (email). Will follow up to see if they have any other specific instructions.
 

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wwhitney

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Electrical User said:
The original post indicates the manufacturer stating, "short radius elbows are only for use right at the box or enclosure and cannot be used in the middle of a conduit run" which I have in writing (email).
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Install a junction box just after the short radius elbow and shorten the 12" horizontal nipple accordingly? Unless the hazardous location rules would prohibit that, I'm unfamiliar with them.

I think the C-condulet suggestion was the same idea, and is more elegant if that would also satisfy the labeling requirements on the short radius elbow.

Cheers, Wayne
 
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