Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 04-24-2009, 07:07 PM   #1
Member
 
Join Date: Nov 2007
Posts: 55
Share |
Default

Wire fill


hi,

i am doing some remodeling, and had to move a 2 gang work box, 2 switches. when i removed the old box, it has one 12-2 feed, and six 12-2 romex feeding outside lights and an outlet. the two gang box was stuffed with wire! is this ok? should i put in a j-box next to the two gang or something to make more room???

bob

bobo60 is offline   Reply With Quote
Old 04-24-2009, 07:48 PM   #2
Member
 
Bigplanz's Avatar
 
Join Date: Apr 2009
Location: Louisville KY
Posts: 508
Default

Wire fill


Quote:
Originally Posted by bobo60 View Post
hi,

i am doing some remodeling, and had to move a 2 gang work box, 2 switches. when i removed the old box, it has one 12-2 feed, and six 12-2 romex feeding outside lights and an outlet. the two gang box was stuffed with wire! is this ok? should i put in a j-box next to the two gang or something to make more room???

bob
Sounds like you need another box, or a box extender. Calculate the size of the box at 2.25 cubic inch per conducter, 2.25 CI for the ground (no matter how many wires), 2.25 CI for the cable clamps. Each hot and neutral entering the box counts as a 'current carrying conductor.' This will tell you how big a box you need. Sounds like 18.25 CI minimum.

Here is a box I found in my house. I just put an extender on it.
Attached Thumbnails
Wire fill-357052783_vzl2n-m.jpg  

Bigplanz is online now   Reply With Quote
Old 04-24-2009, 08:23 PM   #3
Member
 
Join Date: Oct 2007
Posts: 2,294
Default

Wire fill


Don't add another JB to the mix, just use the biggest box you can.

A 2 gang plastic nail on box will accept the wiring if it is done neatly. It's all about the make up. Inexperienced people can fill up a box with four cables where an experienced person could easily double that.

Open anothee stock 2 gang switchbox and take note of how the electrician made up the wiring and follow his methods.
220/221 is offline   Reply With Quote
Old 04-24-2009, 09:14 PM   #4
Member
 
Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Default

Wire fill


Quote:
Originally Posted by Bigplanz View Post
Sounds like you need another box, or a box extender. Calculate the size of the box at 2.25 cubic inch per conducter, 2.25 CI for the ground (no matter how many wires), 2.25 CI for the cable clamps. Each hot and neutral entering the box counts as a 'current carrying conductor.' This will tell you how big a box you need. Sounds like 18.25 CI minimum.
One feed & 6 12-2's - that's 7 wires + 2 switches

Ground = 2.25
Hots = 7 * 2.25 = 15.75
Switches 2 * 2.25 = 4.5
Neutrals = 7 * 2.25 = 15.75
***************************
= 38.25 - that's a lot....if my math is right

or does a device count as 2 (I think?), so 4 * 2.25 = 9
A total of 42.75....THAT is a LOT

I think the quad plastic blue box is rated at 32 ??

Plastic box, metal box? - does it have cable clamps?
Scuba_Dave is offline   Reply With Quote
Old 04-24-2009, 09:15 PM   #5
Licensed electrician
 
Join Date: Sep 2007
Location: Maryland
Posts: 7,410
Default

Wire fill


Six 2 wire cables out and a 2 wire in would be 15 conductor allowances plus the devices. Add 4 for the 2 switches = 19.
19 x 2.25 = 42.75 cubic inches. IIRC a plastic 2g = about 35 cu. in.
Jim Port is offline   Reply With Quote
Old 04-24-2009, 09:21 PM   #6
Member
 
Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Default

Wire fill


I had to go check
The blue Carlton box I have is rated at 32
Scuba_Dave is offline   Reply With Quote
Old 04-25-2009, 02:03 PM   #7
Member
 
Join Date: Oct 2007
Posts: 2,294
Default

Wire fill


Quote:
19 x 2.25 = 42.75 cubic inches. IIRC a plastic 2g = about 35 cu. in.
Quote:
The blue Carlton box I have is rated at 32
32 is about 35
220/221 is offline   Reply With Quote
Old 04-25-2009, 02:21 PM   #8
Member
 
Bigplanz's Avatar
 
Join Date: Apr 2009
Location: Louisville KY
Posts: 508
Default

Wire fill


Quote:
Originally Posted by Scuba_Dave View Post
One feed & 6 12-2's - that's 7 wires + 2 switches

Ground = 2.25
Hots = 7 * 2.25 = 15.75
Switches 2 * 2.25 = 4.5
Neutrals = 7 * 2.25 = 15.75
***************************
= 38.25 - that's a lot....if my math is right

or does a device count as 2 (I think?), so 4 * 2.25 = 9
A total of 42.75....THAT is a LOT

I think the quad plastic blue box is rated at 32 ??

Plastic box, metal box? - does it have cable clamps?
Ok, so my math was way off.

I'll do my math first from now on.
Bigplanz is online now   Reply With Quote
Old 04-25-2009, 04:45 PM   #9
Electrical Contractor
 
kbsparky's Avatar
 
Join Date: Sep 2008
Location: Delmarva
Posts: 3,361
Default

Wire fill


The 2-gang plastic boxes I use are 36 cu in.

Here is a metal one that has 45 cubic inch capacity. You might want to consider using one of these:

kbsparky is online now   Reply With Quote
Old 04-25-2009, 07:42 PM   #10
Member
 
Join Date: Nov 2007
Posts: 55
Default

Wire fill


hi,

thanks for all the ideas! i bought a plastic zip box that is about 3/4" deeper than the original box. not sure of the cu in. i made sure all the wires, blacks, whites and grounds were not tangled in anyway, wired in the switches, wire nutted and tucked away in the back of box, worked out quite well.

bobo60 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
How do I wire my Furnace Fan to kick in and maintain humidity levels? Tryvidy HVAC 1 04-23-2009 11:10 AM
wire running question ponch37300 Electrical 4 04-21-2009 03:58 PM
Burial wire and a seeming difference of opinion... SxS Electrical 19 02-24-2009 09:16 AM
Red wire is HOT genner Electrical 15 02-22-2009 08:14 PM
Running Wire Bocolo Electrical 11 01-24-2009 11:56 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.