ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 255 guests, and 16 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 2 of 2 1 2
Joined: May 2005
Posts: 706
T
Member
What about derating???

Dave

Stay up to Code with the Latest NEC:


>> 2023 NEC & Related Reference & Exam Prep
2023 NEC & Related Reference & Study Guides

Pass Your Exam the FIRST TIME with the Latest NEC & Exam Prep

>> 2020 NEC & Related Reference & Study Guides
 

Joined: Oct 2004
Posts: 806
Member
Originally Posted by Tiger
What about derating???

Dave


If the conduit is under 24", it doesn't need to be derated, right?


Joined: Jan 2003
Posts: 4,391
I
Moderator
Originally Posted by Tiger
What about derating???

Dave


If the section of pipe is less than 24" no derating needed.

If the pipe is longer then 24" the derating must be done but will not change anything until you get past 9 current carrying conductors with 15, 20 and 30 amp circuits.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
I do find it interesting that if you stuff some insulation in the hole in a top plate you need to derate RX but you can stuff a stack like this with duct seal or some other inspecified material without derating.
Things that make you go "huh?".


Greg Fretwell
Page 2 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5