Flexible Cord ampacity

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maallen

Member
Location
Richland, WA
Bear with me on this one. NEC 2002 Tables 400.5(A) & (B) give cord ampacities for various cord types. Below Table 400.5(B) are notes. My question has mostly to do with notes 2 and 3 which give a condition of the ampacities applying to connection to utilization equipment. On a construction site where cords are permitted for feeders and branch circuits cords are often attached to distribution equipment such as disconnect switches.

(1) On a construction site are the cord ampacities given in tables 5(A) and 5(B) applicable only when connected to utilization equipment ?

(2) If not, do I then have to use table 310.16 when connecting to a panel or disconnect as it appears to require in 110.14 (C)(1) ?

(3) Why are the ampacities given in Tables 400.5(A) & (B) only permissible for utilization equipment?:?
 

iwire

Moderator
Staff member
Location
Massachusetts
I do not read it that way at all.

In my opinion those notes do not require the cord to directly feed or be directly connected to utilization equipment.
 

maallen

Member
Location
Richland, WA
I do not read it that way at all.

In my opinion those notes do not require the cord to directly feed or be directly connected to utilization equipment.

I agree the cords are not required to be connected to utilization equipment but the notes do say that the ampacities given are for utilization equipment connection.
 

iwire

Moderator
Staff member
Location
Massachusetts
I agree the cords are not required to be connected to utilization equipment but the notes do say that the ampacities given are for utilization equipment connection.

And that remains the same regardless if there is a panel and branch circuits involved.

I really believe you are over thinking the notes.
 

maallen

Member
Location
Richland, WA
And that remains the same regardless if there is a panel and branch circuits involved.

I really believe you are over thinking the notes.

If I am "over thinking" the notes what then do I do with them? Ignore them? They have to mean something. Therefore, what are they there for?

I really need a solid answer if anyone has one. thanks
 

fmtjfw

Senior Member
If I am "over thinking" the notes what then do I do with them? Ignore them? They have to mean something. Therefore, what are they there for?

The electrons don't know if they are feeding a subpanel, a welder, or a really big light. Why would you expect the ratings to differ?

Sounds like a good change for 2017 to omit utilization equipment from the notes.
 

iwire

Moderator
Staff member
Location
Massachusetts
If I am "over thinking" the notes what then do I do with them? Ignore them? They have to mean something. Therefore, what are they there for?

In my opinion the notes are there only to address the number of current carrying conductors.

2011 NEC
1 The ampacities under subheading D shall be permitted for single-conductor Types SC, SCE, SCT, PPE, and
W cable only where the individual conductors are not installed in raceways and are not in physical contact
with each other except in lengths not to exceed 600 mm (24 in.) where passing through the wall of an
enclosure.

2 The ampacities under subheading E apply to two-conductor cables and other multiconductor cables connected
to utilization equipment so that only two conductors are current-carrying.

3 The ampacities under subheading F apply to three-conductor cables and other multiconductor cables connected
to utilization equipment so that only three conductors are current-carrying.

In my opinion you are overextending what the notes are telling us.
 

maallen

Member
Location
Richland, WA
The electrons don't know if they are feeding a subpanel, a welder, or a really big light. Why would you expect the ratings to differ?

Sounds like a good change for 2017 to omit utilization equipment from the notes.

110.14 identifies provisions for equipment termination temperatures. I think that may be the only issue. I agree the cord does not know what it is terminated on. The notes are frustrating me because I am running up against opposition when trying to apply some common sense such as what has been posted here. And I do appreciate your opinions, BTW.
 
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