ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
Israel
by annemarie1. 04/18/19 02:35 PM
Welded Copper Connections
by gfretwell. 04/17/19 10:03 PM
Water heater calculationsSo when I count calculati
by watersparkfalls. 04/13/19 12:43 PM
Health Canada Electric Construction heaters recall
by dougwells. 04/12/19 01:22 AM
Burning out of return(white) side of 120volt rec
by richard. 04/08/19 07:12 PM
New in the Gallery:
What is this for?
Plug terminals
Who's Online Now
0 registered members (), 14 guests, and 9 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
raceway fill #53623
06/30/05 06:52 PM
06/30/05 06:52 PM
D
drgnz23  Offline OP
Member
Joined: Feb 2002
Posts: 56
los angeles
I having a discussion with one of the older guys about conductors in a 1/2 conduit. I look it up in the code book but its kind of confusing. For example (SIMPLE) 1/2 emt only 9 thhn wires .Is one of those a ground?

Work Gear for Electricians and the Trades
Re: raceway fill #53624
06/30/05 06:55 PM
06/30/05 06:55 PM
R
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
The wire fill is a physical count of the wires in the raceway. What function the wires serve does not enter into this.
Don


Don(resqcapt19)
Re: raceway fill #53625
07/01/05 11:12 AM
07/01/05 11:12 AM
Radar  Offline
Member
Joined: Apr 2004
Posts: 349
Los Angeles, CA
This information is based on Table 1 in Chapter 9 of the NEC, which specifies maximum raceway fill:

53% max for a single conductor in the raceway (i.e. - grounding conductor)
31% max for two conductors
40% for 3 or more conductors

The unused volume of air space within the raceway is needed for cooling of the conductors which tend to warm up due to conductor heating caused by current flow thru the circuit conductors. Overstuffing a raceway, aside from making for a difficult pull, would contribute to conductor overheating by reducing the cooling medium.

Radar


There are 10 types of people. Those who know binary, and those who don't.

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
JoeKP
JoeKP
Berkley, MA
Posts: 144
Joined: March 2008
Show All Member Profiles 
Top Posters(30 Days)
Popular Topics(Views)
254,420 Are you busy
190,669 Re: Forum
180,390 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.015s Queries: 14 (0.004s) Memory: 0.9506 MB (Peak: 1.0747 MB) Zlib enabled. Server Time: 2019-04-18 23:16:19 UTC