ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

ECN Shout Chat
Top Posters(30 Days)
Admin 16
Recent Posts
ESA Arc flash course
by TheShockDoctors. 03/24/17 10:15 AM
fuse rejectors
by HotLine1. 03/24/17 07:53 AM
Another Forum Update
by Admin. 03/22/17 03:04 PM
Dining room plugs
by watersparkfalls. 03/21/17 10:31 PM
TRUE POWER
by jraef. 03/21/17 09:13 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
231,369 Are you busy
166,092 Re: Forum
160,560 Need opinion
Who's Online Now
0 registered members (), 59 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#77085 - 04/20/01 10:52 AM Code Enforcement Overkill?  
Pete  Offline
Junior Member
Joined: Apr 2001
Posts: 1
Built a metal building, with office inside with metal studs. No wood anywhere. Bldg & studs are grounded. Each receptacle has its own grounding lead. Our code enforcement inspector says each junction box must also have a grounding lug. Further, any rigid metal conduit with more than 3 load carrying conductors, conductors must be derated. So, if a 2" conduit has 4 conductors, the wire must be oversized. I'd appreciate comments.


2017 / 2014 NEC & Related Books and Study Guides

#77086 - 04/20/01 11:03 AM Re: Code Enforcement Overkill?  
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
Pete,
250-148(a) requires the EGC to be connected to the box. Table 310-15(b)(2)(a) requires derating of conductors for more than 3 current carrying conductors. Remember that is you are using THHN you can use the 90°C ampacity for derating purposes.
Don(resqcapt19)


Don(resqcapt19)

#77087 - 04/20/01 06:47 PM Re: Code Enforcement Overkill?  
Tom  Offline
Member
Joined: Jan 2001
Posts: 1,044
Shinnston, WV USA
Pete,

Don's reply is right on the money. With THHN insulation in a dry location, you usually don't have a derating problem (at least in the smaller sizes) until you get to the 10th conductor.

Tom


Few things are harder to put up with than the annoyance of a good example.


Member Spotlight
BEAMEUP
BEAMEUP
WA
Posts: 27
Joined: December 2004
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.009s Queries: 14 (0.002s) Memory: 0.7496 MB (Peak: 0.8738 MB) Zlib enabled. Server Time: 2017-03-25 01:57:39 UTC