ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Potseal 11
Recent Posts
600 KW 120/208 3 Phase Y protection
by HotLine1. 07/20/17 10:44 AM
Green House wiring
by ghost307. 07/20/17 09:10 AM
1913 American Electrician's Handbook
by Potseal. 07/20/17 08:42 AM
Permit Snafus...AHJs and Contractors Jump in
by HotLine1. 07/18/17 08:06 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
239,164 Are you busy
174,549 Re: Forum
166,985 Need opinion
Who's Online Now
0 registered members (), 41 guests, and 9 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#80168 - 03/11/02 10:37 PM 16 Gauge Wire ?  
WireWrestler  Offline
Member
Joined: Oct 2001
Posts: 45
Northern IL
I went to a service call lately to a medical office to add some isolated ground circuits for computers. I was shocked to find that the majority of the wiring, more than thirty 110V circuits, was done in 16ga MTW/THHN in EMT on 15 amp breakers. The service is 200 amp single phase and there are no problems with the installation of the service equipment or the load center. The building is less than 10 years old. It is in an area where there are no inspections or licensing required. I was taught to never use less than 12ga wire in commercial buildings and that is what I have always done but I can't find the code to back it up. I want some really solid ground to approach the owners with to convince them to do something about it. Can anyone help me with code references? Thanks!


2017 / 2014 NEC & Related Books and Study Guides

#80169 - 03/11/02 11:05 PM Re: 16 Gauge Wire ?  
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,878
NY, USA
WW,

Although 12 ga minimum is a good policy to go by I don't know of any rules requiring that. There is one though that specifies 14 ga minimum see 310.5

Bill


#80170 - 03/11/02 11:56 PM Re: 16 Gauge Wire ?  
WireWrestler  Offline
Member
Joined: Oct 2001
Posts: 45
Northern IL
Bill, I saw that and my interpetation was that anything smaller than 14ga could only be used in fixtures and control panels but not for fixed wiring in a building. The ampacity of the 16ga THHN is 18 amps, so I guess it is not overloaded, but it still seems very strange to me. The 12ga minimum size for commercial buildings may have been a local code in places I have worked over the years and it just stuck with me. Thanks for the reply.


#80171 - 03/12/02 12:31 AM Re: 16 Gauge Wire ?  
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,878
NY, USA
Quote
my interpetation was that anything smaller than 14ga could only be used in fixtures and control panels but not for fixed wiring in a building.


Your statement is correct. 16 ga should not be used for the wiring in this building. In Table 310.16 that 18a you see is under the 90C column and that could only be used if wiring was connected to terminals with a rating of 90C. Breakers are either 60C or 75C (some older ones even 40C) If you notice, there is no ampacity under the 60C and 75C columns for 16ga wire.

Bill

[This message has been edited by Bill Addiss (edited 03-11-2002).]


#80172 - 03/13/02 10:17 PM Re: 16 Gauge Wire ?  
Ron  Offline
Member
Joined: Mar 2002
Posts: 582
White Plains, NY
240.4(D) limits 15 ampere max. overcurrent protection for #14 awg.


Ron


Member Spotlight
Grover
Grover
Sebago, ME, USA
Posts: 109
Joined: January 2005
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: 0.020s Queries: 14 (0.002s) Memory: 0.7684 MB (Peak: 0.9061 MB) Zlib enabled. Server Time: 2017-07-20 16:47:50 UTC