Larrym
Member
- Location
- Metarie, Louisiana
When was 310.15(B) added to the NFPA 70 code book?
Conductor derating for more then 3 current carring conductors
- Thread starter Larrym
- Start date
- Status
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
It is in my 1951. You need to go back further?
Larrym
Member
- Location
- Metarie, Louisiana
310.15.B (2) Adjustment factors
310.15.B (2) Adjustment factors
I am looking for the edition that added 310.15.B (2) Adjustment factors to the NEC.
310.15.B (2) Adjustment factors
I am looking for the edition that added 310.15.B (2) Adjustment factors to the NEC.
- Location
- Illinois
- Occupation
- retired electrician
In the 93 and earlier codes that would have been Note 6 to the 0 to 2000 volt ampacity tables.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Any specific factors you are wanting to know about? Or specific code year you are talking about? 310.15(B)(2) is different in 2008 than in 2011.
Ambient temp correction is what you get in 2011 - this used to be at bottom of ampacity tables.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
According to Don's post it was added in 1996.
As mentioned is there any specific reason why this year is important?
As mentioned is there any specific reason why this year is important?
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I didn't take what Don said to mean iy was 1996. I think he meant that before 1996 it was listed as Note 6 not 310.15(B)(2). My impression is it is still there in 1993 esp. since jumper stated it is in 1951 NEC
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
IDK what the OP wants at this point.
1. When was that exact table formed and numbered that way?
or
2. When was derating for more than 3 CCCs first required?
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
My guess is #2
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Well, I am gonna leave that to Al or Ken. I have a 1940 and a 1923, but they are packed away.
OP can search the NFPA archives if he really needs this info, I ain't that ambitious today.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
I thought that the OP was asking when the table was added.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
You may be right but I inferred he wanted to know when the de-rating came into effect not the specific table in that section.
- Status