SER in cable tray

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stonecutter

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Michigan
Lots and lots of SE being run in cable tray that is mounted in the ceiling hallways of an apartment building. The SE cables do not have "CT" or any other listing on the cable itself that qualifies it for being used in cable tray. NEC 2011 Art. 338.10 does not list SE being listed as a permitted use in cable trays. Although, NEC 2011 Art. 392.10 does list "service conductors' as being permitted in a cable tray as a support system. But, do they still need to be listed for use in cable tray?
 

augie47

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Tennessee
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State Electrical Inspector (Retired)
IMO, 392.10 would allow the SE and no extra listing or marking would be required, however, 338.10(4)(a) required the SE to follow the rules for Art 334. Will 334.12(A) cause you a problem ?
 

don_resqcapt19

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The "CT" marking is only required for single conductors, and not for a cable assembly. Table 392.10(A) shows all of the wiring methods that are permitted to be used in cable tray. SE is shown in the 2014 version of that table.
 

augie47

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The "CT" marking is only required for single conductors, and not for a cable assembly. Table 392.10(A) shows all of the wiring methods that are permitted to be used in cable tray. SE is shown in the 2014 version of that table.
don, I'm trying to picture a compliant way this method could be used in a multifamily structure.
If would seem if the SE was in an exposed tray or above a drop or suspended ceiling it would be a violation of 338.10, 334.12. Comment ?
 

stonecutter

Member
Location
Michigan
Interesting that is listed in NEC 2014. We just adopted the 14 code June 18. Unfortunately, the permit was secured before that date. I'll verify the rating of the hallways. The ceilings are not dropped, or suspended. They will be dry walled. I will also check if the ceiling will be insulated in any way, bringing the ampacity rating to the 60 degree rating.
 

don_resqcapt19

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Location
Illinois
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don, I'm trying to picture a compliant way this method could be used in a multifamily structure.
If would seem if the SE was in an exposed tray or above a drop or suspended ceiling it would be a violation of 338.10, 334.12. Comment ?
Augie, you are correct. I did not look at that part. 338.10(B)(4)(a) requires compliance with Part II of Article 334 and 334.12 is in Part II.
 

don_resqcapt19

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Location
Illinois
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retired electrician
Interesting that is listed in NEC 2014. We just adopted the 14 code June 18. Unfortunately, the permit was secured before that date. I'll verify the rating of the hallways. The ceilings are not dropped, or suspended. They will be dry walled. I will also check if the ceiling will be insulated in any way, bringing the ampacity rating to the 60 degree rating.
How are you going to have compliance with 392.18(E)?
 

Smart $

Esteemed Member
Location
Ohio
... I'll verify the rating of the hallways. The ceilings are not dropped, or suspended. They will be dry walled. I will also check if the ceiling will be insulated in any way, bringing the ampacity rating to the 60 degree rating.
I'm having a problem with this description.

If the ceiling is not dropped or suspended and will be drywalled [hardtop], how does the ceiling being insulated or not affect the cable? And if the tray is going to be above the drywall, how is the tray installed and still permit access after the drywall is up [392.18(E)]???

E2+: Don must have posted while I was reading.... :sleep:
 

Smart $

Esteemed Member
Location
Ohio
don, I'm trying to picture a compliant way this method could be used in a multifamily structure.
If would seem if the SE was in an exposed tray or above a drop or suspended ceiling it would be a violation of 338.10, 334.12. Comment ?

Augie, you are correct. I did not look at that part. 338.10(B)(4)(a) requires compliance with Part II of Article 334 and 334.12 is in Part II.
Exactly what part of 334.12 are we looking at? The way I see it, SER is not an NM type, so none of 334.12 applies.
 

don_resqcapt19

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Location
Illinois
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retired electrician
Exactly what part of 334.12 are we looking at? The way I see it, SER is not an NM type, so none of 334.12 applies.
Did you read the section that I cited? 338.10(B)(4)(a). It appears to me that for this application the rules in Part II of Article 334 apply.
 

Smart $

Esteemed Member
Location
Ohio
I believe 338.10(B)(4) requires compliance with 334.12
See below...

Did you read the section that I cited? 338.10(B)(4)(a). It appears to me that for this application the rules in Part II of Article 334 apply.
I'm not saying it doesn't. I guess it's more that I tend to read requirements as explicit and everything in 334.12 is regarding Type NM... nothing about Type SE.
 

iwire

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Location
Massachusetts
I'm not saying it doesn't. I guess it's more that I tend to read requirements as explicit and everything in 334.12 is regarding Type NM... nothing about Type SE.

Huh? :?:blink:


The entire article is specifically about NM and not SE. I am missing the point you trying to make.
 

Smart $

Esteemed Member
Location
Ohio
Huh? :?:blink:


The entire article is specifically about NM and not SE. I am missing the point you trying to make.
No, you got the point, you're just not seeing it. I wouldn't have a problem if the 334 sections did not specifically use the words Type NM, NMC, and NMS or such. For example, 334.12(A) should just state, "Cables shall not be permitted as follows:" or contain statement(s) or clause(s) to the effect it applies to interior Type SE. Let's table that for another time.

What part of the OP's installation would violate 334.12?
 

don_resqcapt19

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Location
Illinois
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retired electrician
No, you got the point, you're just not seeing it. I wouldn't have a problem if the 334 sections did not specifically use the words Type NM, NMC, and NMS or such. For example, 334.12(A) should just state, "Cables shall not be permitted as follows:" or contain statement(s) or clause(s) to the effect it applies to interior Type SE. Let's table that for another time.

What part of the OP's installation would violate 334.12?
I don't see how they can make it any clearer.
...Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334, excluding 334.80.
334.12 is an installation requirement.

As far as what, part, that was based on the original assumption that the hallway ceilings were lay in tile. Now that we are told that the are drywall, the issue goes away as cable tray is not permitted about a "hard" ceiling unless there is access.

There is no reason why the SE can't be installed above the hard ceiling, but it just can't be in cable tray.
 

Smart $

Esteemed Member
Location
Ohio
I don't see how they can make it any clearer. ...
They could say...
Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334 for Type NM [or NMC, or NMS], excluding 334.80.
We know article 334 is for Type NM, but then why does practically every section repeat Type NM, NMC, and NMS?

If I say the condition below applies to Type SE, does it apply?
If I say the condition for Type NM below applies to Type SE, does it apply?
Type NM shall not be permitted exposed in dropped ceilings.
 

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
They could say...

We know article 334 is for Type NM, but then why does practically every section repeat Type NM, NMC, and NMS?

If I say the condition below applies to Type SE, does it apply?
If I say the condition for Type NM below applies to Type SE, does it apply?
We are not going to agree on this. There is no reason for the NM article to reference other cable types. The SE article does that. All of the rules in Part II of Article 334 apply to where it is being used for interior wiring. For all practical purposes the rule in 338 is saying that SE becomes NM where used in an interior location.
 
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