ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Recent Posts
VFD MotorFeeders
by gfretwell. 10/19/17 01:02 AM
Generator Cable Sizing
by brsele. 10/18/17 07:39 PM
What do you do?
by gfretwell. 10/17/17 01:08 AM
Good ol' copper pipe in the fuse holder trick
by HotLine1. 10/16/17 07:16 PM
Another generator question
by HotLine1. 10/16/17 07:02 PM
New in the Gallery:
Gallery Test
Popular Topics(Views)
241,415 Are you busy
177,389 Re: Forum
168,987 Need opinion
Who's Online Now
1 registered members (brsele), 21 guests, and 10 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#97487 - 02/22/06 08:55 PM supplemental grounding electrode  
gserve  Offline
Member
Joined: Mar 2003
Posts: 92
1)When a ufer ground is installed is a supplemental electrode required? (2) If one is required do I need 2 rods and do they have to be 6' min away from each other and the foundation?(as this is used for an electrode)(3)Can the #4 grounding electrode conductor be run through bored holes in the 2x10's to the panel?


2017 / 2014 NEC & Related Books and Study Guides

#97488 - 02/22/06 09:31 PM Re: supplemental grounding electrode  
renosteinke  Offline
Cat Servant
Member
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
I remember reading Mr. Ufer's reports on his grounding electrode. Under extremely adverse conditions, his method always performed far better than the 25 ohms code calls for. This was confirmed by Max Macomb, in his documentation that finally persuaded the code panels to accept the "Ufer ground."

If you're measuring over 25 ohms, I would suspect a problem with the measurement method.

But, there is no rule agains adding an electrode if you want to....but it needs to be six feet, or more, from the Ufer...which, in this case, means the entire slab. With a "Ufer," your slab is the electrode- not just that little copper wire!

While many measure the resistance of the ground by simply sticking their meter probe in the dirt....there has to be a reason for those pricey clamp-on meters, and other fancy equipment, used to measure grounding impedence.


#97489 - 02/22/06 09:47 PM Re: supplemental grounding electrode  
HotLine1  Offline


Member
Joined: Apr 2002
Posts: 6,872
Brick, NJ USA
Gserve:
In NEW construction, where a footing/foundation is being installed...it is mandatory that a Ufer be installed.

With a Ufer, no supplemental electrodes are required. (You may if you choose; they must be bonded together)

Yes, you may route the GEC thru wood framing.

As to the 'spacing'; IF you install, 6' spacing, like Reno stated above.

PS: You also have to 'bond' the water piping, jump the meter, bond the H&C at the wtr htr, etc.

John


John


Member Spotlight
akmaster
akmaster
alaska
Posts: 70
Joined: June 2012
Show All Member Profiles 
Featured:

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

 

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.011s Queries: 14 (0.003s) Memory: 0.7538 MB (Peak: 0.8769 MB) Zlib enabled. Server Time: 2017-10-20 23:25:30 UTC