ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
UL 508A SPACING
by ale348 - 03/29/24 01:09 AM
Increasing demand factors in residential
by tortuga - 03/28/24 05:57 PM
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
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
1 members (ale348), 302 guests, and 14 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#95181 09/03/05 08:55 PM
Joined: Aug 2005
Posts: 64
K
Member
Could anyone help me determine the fill on the blue plastic nail on box(4"x2"). Sometimes I have been in the situation where I needed to pull 4 12/2 w/G's in the blue box to connect to other circuits. I only count all the grounds 1 time, each individual conductor 1 time, the yoke (switch or receptacle) 2 times and each wire nut (clamp) 1 time. When I total this up it's 8 wires, 1 ground, 3 wire nuts, and 2 for the yoke. Total 14. I have seen this done many times in other jobs but it seems to be ok with most inspectors. Does anyone have some good input on this?

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
 

#95182 09/03/05 09:08 PM
Joined: May 2004
Posts: 73
R
Member
IMHO the wire nuts aren't clamps so you don't count them. If you don't put in a device (just a blank cover) you get 2 more back. It should end up being 8 wires plus 1 ground for a total of 9 (or 11 with a device).

#95183 09/03/05 09:31 PM
Joined: Jul 2004
Posts: 9,923
Likes: 32
G
Member
The biggest single gang carlon nailup I have seen is the 3¼ deep and that is 22 cu/in, That is still too small for 11 #12s. (9 wires and the device)

2¼ x 11 = 24.75


Greg Fretwell
#95184 09/05/05 01:09 AM
Joined: Jun 2005
Posts: 91
G
Member
Quote
Sometimes I have been in the situation where I needed to pull 4 12/2 w/G's in the blue box to connect to other circuits. I only count all the grounds 1 time, each individual conductor 1 time, the yoke (switch or receptacle) 2 times and each wire nut (clamp) 1 time.
As mentioned above, wire nuts are not clamps. See 314.16.

Clamps attach the cable to the box, not conductors together. [Linked Image]

The easiest way to keep these things straight when first getting them straight, IMO, is to go down the list one by one:

So 4 12-2's with 1 device are
8 insulated conductors (314.16(B)(1))
0 Clamps (314.16(B)(2))
0 Support Fittings (314.16(B)(3))
2 counts for 1 device (314.16(B)(4))
1 count for all EGC's (314.16(B)(5))


Is 11 conductors x 2.25 = 24.75 cu.in.

That's way over for a single gang, even Carlon. (gfret, box fill is something best understood when the same math is done four different ways. [Linked Image] )


-George
#95185 09/05/05 08:26 AM
Joined: Mar 2003
Posts: 29
M
Member
And for those of us whose arithmeticer's don't work so good, Carlon boxes have the maximum number of each size conductor marked in the back of the box. Takes the guesswork out of it if you're not handy with the math.

#95186 09/05/05 08:40 AM
Joined: Jan 2003
Posts: 4,391
I
Moderator
Nice job Just George


You got sucked in didn't you?

Don't blame me. [Linked Image]


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#95187 09/05/05 10:11 AM
Joined: Jun 2005
Posts: 91
G
Member
Well, I ran out of stuff to do at my normal haunt. [Linked Image]

Everybody's enjoying their three-day weekend. Did you see me hanging off the rock?

-George S.


-George

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