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sparky89
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9 Posts
Discussion Starter #1
Hi All,
Just double checking befor I buy some cut wire! ;-)
I am running a 100 amp sub panel (indoor) from a 200 amp service.
55' run. I have a dryer 30 amp and 4 20's possibly a couple of lighting circuits. What size of aluminum romex should I buy? Thanks.
 

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Lic Electrical Inspector
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1,843 Posts

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Electromagician
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79 Posts
can I get that code reference that ser can only be used at 60 C. :whistling2:
 

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Lic Electrical Inspector
Joined
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1,843 Posts
can I get that code reference that ser can only be used at 60 C. :whistling2:
II. Installation
338.10 Uses Permitted.


(B) Branch Circuits or Feeders.


(4) Installation Methods for Branch Circuits and Feeders.


(a) Interior Installations. In addition to the provisions of this article, Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334.
FPN: See 310.10 for temperature limitation of conductors.


334.80 Ampacity.


The ampacity of Types NM, NMC, and NMS cable shall be determined in accordance with 310.15.
The ampacity shall be in accordance with the 60°C (140°F) conductor temperature rating. The 90°C (194°F) rating shall be permitted to be used for ampacity derating purposes, provided the final derated ampacity does not exceed that for a 60°C (140°F) rated conductor. The ampacity of Types NM, NMC, and NMS cable installed in cable tray shall be determined in accordance with 392.11.

Table 310.16 60 degree column, #2 AL = 75 amps.

 

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Licensed Electrical Cont.
Joined
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7,829 Posts
can I get that code reference that ser can only be used at 60 C. :whistling2:
Here is the footnote from the NEC Plus 2008:
Changed From 2005

•Changed From 2005
338.10(B)(4)(a): Deleted the clause “excluding 334.80” to clarify that that section applies when determining the ampacity of Type SE cable when used for feeders and branch circuits in interior wiring installations.
 

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Licensed Electrical Cont.
Joined
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7,829 Posts
can I get that code reference that ser can only be used at 60 C. :whistling2:
What's the most recent copy of the NEC that you have?? :whistling2:
 

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Electromagician
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79 Posts
2011 what does that have to do with the question???? :whistling2:
 

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" Euro " electrician
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5,369 Posts
Not everyone will use the 2011 NEC code right away so just be aware that some states just got 2005 and some just got on 2008 so you will have to use the 2005 and 2008 NEC code cycle to get up to the speed.

Many of the electricians whom are on here for quite a while we will have few older editions of NEC as referince point plus what more is that some states will have some local change to the codes.

Merci,
Marc
 

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Electromagician
Joined
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79 Posts
look I don't care if it's 2002, 2005, 2008, 2011 but no one has given any reference for ser only being allowed at 60 degrees C. :whistling2: I have been told by several here that I am wrong and that is the case. So stop acting like an inspector and spill the reference.
 

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Master Electrician
Joined
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4,641 Posts
look I don't care if it's 2002, 2005, 2008, 2011 but no one has given any reference for ser only being allowed at 60 degrees C. :whistling2: I have been told by several here that I am wrong and that is the case. So stop acting like an inspector and spill the reference.
See posting # 7.
 

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Electromagician
Joined
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79 Posts
Where is the reference?????? I don't see anything here!
II. Installation

338.10 Uses Permitted.rticle


(B) Branch Circuits or Feeders.

(4) Installation Methods for Branch Circuits and Feeders.


(a) Interior Installations. In addition to the provisions of this article, Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334.
FPN: See 310.10 for temperature limitation of conductors.



Article 338 specifically excludes 334.80 which is about NM anyway.


334.80 Ampacity.


The ampacity of Types NM, NMC, and NMS cable shall be determined in accordance with 310.15.

The ampacity shall be in accordance with the 60°C (140°F) conductor temperature rating. The 90°C (194°F) rating shall be permitted to be used for ampacity derating purposes, provided the final derated ampacity does not exceed that for a 60°C (140°F) rated conductor. The ampacity of Types NM, NMC, and NMS cable installed in cable tray shall be determined in accordance with 392.11.


Table 310.16 90 degree column #2 AL = 90 amps. so what?


Table 310.16 60 degree column, #2 AL = 75 amps.


So does anyone have the reference? please print the part where it actually says you are limited to only using ser aluminum at the 60 degree rating.
 

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Master Electrician
Joined
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4,641 Posts
SER is to be installed compliant with article 334 which covers NM. NM is limited to 60 degree ampacity. It therefore follows that SER used for interior installations is limited to 60 degree C ampacity. Which part don't you understand? It's right there in bold, black italic print.
 

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Electromagician
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79 Posts
this is as much fun as an inspection :furious: :no: :eek: :yes::yes: :no: :furious: :( :)
 

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Electromagician
Joined
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79 Posts
SER is to be installed compliant with article 334 which covers NM. NM is limited to 60 degree ampacity. It therefore follows that SER used for interior installations is limited to 60 degree C ampacity. Which part don't you understand? It's right there in bold, black italic print.
do you really believe what you just wrote???? maybe you should read 338 again :yes:
 

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Licensed Electrical Cont.
Joined
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7,829 Posts
powerfactor, I am not believing what YOU are writing.
Now you are just being a troll.

If you cannot see what is plainly in front of your face then you have NO right calling yourself an electrician.

Posts #7 and #8 CLEARLY state this.

338.10 says SE cable used as a feeder or branch circuit must comply with Part II of Art. 334.
334.80, which is in Part II, states that "The ampacity shall be in accordance with the 60°C (140°F) conductor temperature rating."

This limit of using the 60 deg C column was not included for SE cable until the 2008 edition.

If you still cannot grasp this then I am done. You simply CHOOSE not to see what is clearly right in front of you.
 
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