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 05-04-2011, 04:36 PM   #31
Electrical Contractor
 
jbfan's Avatar
 
Join Date: Jun 2004
Location: Newnan GA
Posts: 5,683
Share |
Default

Subpanel conductors


Doesn't matter if it is a main lug, or main breaker panel.
A ground rod is for lighting protection only.

__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"
jbfan is offline   Reply With Quote
The Following 2 Users Say Thank You to jbfan For This Useful Post:
downunder (05-05-2011), junkcollector (05-04-2011)
Old 05-04-2011, 05:02 PM   #32
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Default

Subpanel conductors


Quote:
Originally Posted by The Deez View Post
right it's a main lug panel( a panel with no main breaker) so all grounding needs to go back to the main panel. It's hard to explain, but basically you can't have 2 sources to ground because it causes a difference in potential between the two, which can and will cause safety risks. it's right in article 250 you typically pound two rods at the MAIN service as a supplemental grounding electrode, or the primary if no cold water pipe is present. sitting through countless hours of boring grounding classes has done me good.
while it's an MLO, it doesn't change a thing. Being an MLO does not alter the physics involved or the code involved.

since you are so convinced of this, please cite the exact code section you believe requires what you are stating. Then I'll post the section that makes your irrelevant.

aw heck, I've never been good at keeping a secret. Check out 250.32(A)
nap is offline   Reply With Quote
Old 05-04-2011, 05:57 PM   #33
licensed electrician
 
Join Date: Jul 2010
Location: Hooksett, New Hampshire
Posts: 45
Default

Subpanel conductors


Quote:
Originally Posted by jbfan View Post
Doesn't matter if it is a main lug, or main breaker panel.
A ground rod is for lighting protection only.
A ground rod is not for lightening protection

and to nap, i seem to have completely missed the fact that he is at a detached building with this sub panel, I just looked at his pictures and fired away, i should of read the post. THAT BEING SAID you are right, you need the ground rod outside to the equipment grounding bar which by the way is still not bonded. don't flame me bro!

Last edited by The Deez; 05-05-2011 at 02:52 PM.
The Deez is offline   Reply With Quote
Old 05-04-2011, 06:21 PM   #34
Lic Elect/Inspector/CPO
 
Join Date: Apr 2011
Location: NJ
Posts: 369
Default

Subpanel conductors


A ground rod or a ground field’s only purpose in life is to have a designed electrical path to dissipate a static discharge voltage (such as Lightning) to earth
NJMarine is offline   Reply With Quote
Old 05-04-2011, 08:18 PM   #35
nap
You talking to me?
 
nap's Avatar
 
Join Date: Dec 2007
Location: sw mi
Posts: 5,407
Default

Subpanel conductors


Quote:
Originally Posted by NJMarine View Post
A ground rod or a ground field’s only purpose in life is to have a designed electrical path to dissipate a static discharge voltage (such as Lightning) to earth
Oh let's not get into this discussion again. Per the code250.4(A)(1)

Electrical System Grounding

Electrical systems that are grounded shall be connected to the earth in a manner that will limit the voltage imposed by lightning, line surges, or unintentional contact with higher-voltage lines and that will stabilize the voltage to earth during normal operation.

So, not only is it intended to be a path for lightning, it is also meant to be a path for essentially all unintended voltages such as if the higher voltage from a high voltage line is imparted upon the lower voltage system for some reason.

as well as to provide a 0 volt reference point for the system.
nap is offline   Reply With Quote
Old 05-04-2011, 08:53 PM   #36
licensed electrician
 
Join Date: Jul 2010
Location: Hooksett, New Hampshire
Posts: 45
Default

Subpanel conductors


the should remove lightning from this article all together don't you think?or am stupid.i mean lets be honest, if lightening hit your house or even close to the ground rods, your f&%@ed
The Deez is offline   Reply With Quote
Old 05-04-2011, 09:04 PM   #37
Floor Sweeper
 
Join Date: Nov 2007
Location: Central MN
Posts: 353
Default

Subpanel conductors


Quote:
A ground rod is not for lightening protection
That is a pretty ignorant statement by someone who claims to be a pro. I wouldn't cause trouble, but the whole idea here is to help these people, and give them correct advice.
junkcollector is offline   Reply With Quote
The Following User Says Thank You to junkcollector For This Useful Post:
downunder (05-05-2011)
Old 05-04-2011, 09:38 PM   #38
Member
 
Missouri Bound's Avatar
 
Join Date: Apr 2011
Location: Almost Arkansas
Posts: 2,764
Default

Subpanel conductors


So downunder....did you get your answer yet or just confused? There is a lot of help here, despite how it looks. Let us know if you can pull those wires out.
Missouri Bound is offline   Reply With Quote
Old 05-05-2011, 07:27 AM   #39
Electrical Contractor
 
jbfan's Avatar
 
Join Date: Jun 2004
Location: Newnan GA
Posts: 5,683
Default

Subpanel conductors


Quote:
Originally Posted by The Deez View Post
A ground rod is not for lightening protection

and to jbfan, i seem to have completely missed the fact that he is at a detached building with this sub panel, I just looked at his pictures and fired away, i should of read the post. THAT BEING SAID you are right, you need the ground rod outside to the equipment grounding bar which by the way is still not bonded. don't flame me bro!
Not a problem.
We are all here to help and learn, I hope!
__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"
jbfan is offline   Reply With Quote
Old 05-05-2011, 02:33 PM   #40
licensed electrician
 
Join Date: Jul 2010
Location: Hooksett, New Hampshire
Posts: 45
Default

Subpanel conductors


Quote:
Originally Posted by junkcollector View Post
That is a pretty ignorant statement by someone who claims to be a pro. I wouldn't cause trouble, but the whole idea here is to help these people, and give them correct advice.
are you for real right now? if anybody thinks that the two ground rods outside connected to somebodies main service with a #6 wirer will protect them from lightening strikes on their house needs to have there head examined. I'm not trying to start anything either, but a ground rod is not for lighting arrest. A lightening arrest system is an engineered grounding grid system with lightening rods.

Last edited by The Deez; 05-05-2011 at 02:51 PM.
The Deez is offline   Reply With Quote
Old 05-05-2011, 05:12 PM   #41
Lic Elect/Inspector/CPO
 
Join Date: Apr 2011
Location: NJ
Posts: 369
Default

Subpanel conductors


Nobody here said it was a lightening arrest system
NJMarine is offline   Reply With Quote
Old 05-05-2011, 06:58 PM   #42
Don't know it all, yet!
 
Join Date: Jun 2008
Location: Metro Atlanta, GA
Posts: 910
Default

Subpanel conductors


Just my experience with lightning strikes, discharges, and ground rods.

I had this house built in 1977. For years, everytime a thunderstorm would come up I could see bright flashes in the yard. One day I was looking out the side door and saw a static discharge bounce off the elbow on the gas meter. That would be pucker factor 99! So now I know why it always looked like someone was standing in the yard making flash photos.

Continuing the saga, one day I decided to put a small flower bed around the utility area- gas meter and the electric meter which is just above. I was digging carefully and discovered that the ground from the meter put a whole new spin on "ground." The wire was stuck in the dirt about a foot. No ground rod at all! After installing a ground rod and actually connecting the ground wire to it, I have since had no more arcing off of the gas meter and light bulbs last a lot longer. That's just my experience- it is what it is.

I also had lightning strike a pine tree a few years ago a few feet from the front porch. I mean about ten feet from the porch and I heard it hiss when it came over the house!!! I USED to like to sit and watch it dance in the clouds. And just for saying it, the clouds were several miles away and the sky was blue above the house. The lightning came from the back of the house opposite from where I was watching the clouds. I don't know where it came from, but I know where it landed.

When I went inside I heard the stereo buzzing but not playing anymore. When my son came home from school, I told him not to turn the stereo on. He came outside a few minutes later and asked if I had been in his room. That same lightning came in there (same side of the house) and literally blew up his stereo. Speakers were exploded into pieces across the room. The outlet was black. Outside I discovered that a nail on the gutter downspout was burned also.
__________________
If it's worth doing, it's worth doing right. If you wouldn't put your name on it, it ain't done right!
downunder is offline   Reply With Quote
Old 05-05-2011, 07:17 PM   #43
Don't know it all, yet!
 
Join Date: Jun 2008
Location: Metro Atlanta, GA
Posts: 910
Default

Subpanel conductors


Replies separated for clarity.

Missouri Bound,

Yes, I see two ways to go now. I'm thinking that since I don't have any plans to use 240v at the present, the simplest thing to do would be:
Use the white hot leg for a neutral.
Add a grounding bus (which I have already bought).


I haven't completely decided whether to add a ground rod at the shop or just use the house ground since this is basically just another room, only detached. I'm speaking from practicality, not code here. We should always wear our seat belts, drive less than 55, and remember the wife's birthday and the anniversary. Right? Well, maybe the last two are code!

And put a nut on the service conduit.

Good day and thanks for all the input.
__________________
If it's worth doing, it's worth doing right. If you wouldn't put your name on it, it ain't done right!
downunder is offline   Reply With Quote
Old 05-05-2011, 08:19 PM   #44
licensed electrician
 
Join Date: Jul 2010
Location: Hooksett, New Hampshire
Posts: 45
Default

Subpanel conductors


in all honesty, the code, especially with article 250 (grounding) is so convoluted. the code constantly contradicts it self from article to article. how ever here is the code that says you need it.

250.32 Buildings or Structures Supplied by a Feeder(s)
or Branch Circuit(s).
(A) Grounding Electrode. Building(s) or structure(s) supplied
by feeder(s) or branch circuit(s) shall have a grounding
electrode or grounding electrode system installed in
accordance with Part III of Article 250. The grounding
electrode conductor(s) shall be connected in accordance
with 250.32(B) or (C). Where there is no existing grounding
electrode, the grounding electrode(s) required in 250.50
shall be installed.

your shed is a structure and the wires going from the house to your shed are feeders, seeing as that they feed a sub panel. so it falls under this code article.

Last edited by The Deez; 05-05-2011 at 08:22 PM.
The Deez is offline   Reply With Quote
Old 05-06-2011, 06:06 PM   #45
Don't know it all, yet!
 
Join Date: Jun 2008
Location: Metro Atlanta, GA
Posts: 910
Default

Subpanel conductors


I just love ambiguous half-truths.

__________________
If it's worth doing, it's worth doing right. If you wouldn't put your name on it, it ain't done right!
downunder 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
Adding a subpanel to a sub-panel and other questions CardinalPilot Electrical 14 03-30-2011 02:23 PM
Grounding a Subpanel Craigman Electrical 25 12-07-2009 07:25 PM
Problems with Square D Subpanel bltglt507 Electrical 16 12-04-2009 08:44 PM
A few slightly different questions on subpanel wiring. Chris Dopp Electrical 8 06-26-2009 09:45 PM
Reverse Polarity at the Subpanel adm060306 Electrical 14 07-09-2007 12:58 PM




Top of Page | View New Posts

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