The Electrical Contractor Network

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

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Correct rotation, wrong sequence
by Potseal
Yesterday at 03:14 PM
Industrail Control Panel bonding per 409.108
by sparkyinak
12/09/16 06:29 PM
Calling all Non-US members!! (Non-US only)
by aussie240
12/07/16 02:39 AM
Photo Upload Tutorial
by DanK
12/06/16 11:35 PM
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 11
HotLine1 10
Potseal 9
sparkyinak 8
Texas_Ranger 7
Who's Online
1 registered (geoff in UK), 205 Guests and 5 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#53623 - 06/30/05 03:52 PM raceway fill
drgnz23 Offline
Member

Registered: 02/17/02
Posts: 56
Loc: 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?

Top
Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#53624 - 06/30/05 03:55 PM Re: raceway fill
resqcapt19 Offline
Member

Registered: 11/10/00
Posts: 2209
Loc: 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)

Top
#53625 - 07/01/05 08:12 AM Re: raceway fill
Radar Offline
Member

Registered: 04/30/04
Posts: 349
Loc: 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.

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals