No Ground in Circuit panel.

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While wiring my shop, I noticed something very disturbing. My house is not grounded. I open my main panel and there are the two hots and one neutral.
Ground bus and neutral bus are connected and both ground and neutral wires share the same bus.
My house is newer, only about 8 years old.
Why is there no ground? I know when I did the same work in FL I was required to put in two ground rods.
Is this a concern or normal?
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Is the ground bus then hooked up to some kind of ground wire? What happens if you insert one of those plug testers into a wall socket -- do you get a green light indicating adequate ground?
Dave

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Yes, that is how a panel is done; ground and neutral are the same bus. On a subpanel they are separated.

There should be a cable going from the ground bus to your ground rods/water pipe. Look carefully. If it is not there, you have a problem; but it seems unlikely.

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If your ground goes to a water pipe check it out a bit. In my previous house I was doing some other remodeling when I discovered that the water line coming into the house had at some point been re-done in plastic. I had a ground to the galvanized pipe in the house, but effectively no real ground since what actually went into the ground was non-conductive. I drove an 8' rod and properly grounded things - it was amazing, both my phone system and my computer worked better after that.
Tim Douglass
http://www.DouglassClan.com
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Its is correct for the main panel. The neutral and ground share the same bus. Only in a sub-panel will the ground be isolated from the neutral bus.
Dave

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On Mon, 01 Nov 2004 07:23:14 -0800, Elmar wrote:

Usually, the neutral is grounded at the transformer, and the meter and entrance panel share a common ground with the neutral in the entrance panel bonded to ground. Any subpanels should have the neutral isolated from ground.
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Son in law discovered the same on their "new" (20yr old) house. Might have been because the subdivision is on an old lakeside dune, and a driven rod would have trouble gaining a ground. His dad, who works for a power company, came up with ten feet of rod to drive. Next time the weather gets dry, we'll see.
Guard tower they built at the airbase, also in sand, had to have an extensive grid buried to keep St Elmo and lightning away.

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This is usually the case with service panels.

There is probably a green wire snaking out to your grounding electrode, usually a rod driven in the ground. It could also be connected to various substitutes for a ground rod that are allowed as well.
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Don't know much about this but it seems like I remember that the code most places prohibits more than one ground. Aren't you required to have a ground for the main service or panel and no secondary ground at any sub panel?
bob g.
Bob Peterson wrote:

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Robert Galloway said:

If the sub-panel is located in a separate building from the main panel, code generally calls for a local ground for the sub-panel.
Greg G.
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<Greg G.> wrote in message

Generally you are required to have another grounding electrode (typically a ground rod) but not necessarily a connection between earth and neutral at that subpanel. the ground rod is for lightning protection.

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Bob Peterson said:

Err... I guess I was unclear/incomplete. It is a convoluted subject, but here is the entire run-down as per the 2002 NEC.
When the sub-panel is located in the same building, you use the ground provided in the main panel, and DO NOT bond the ground and neutral together in the sub-panel - requiring a 4 wire feed.
A detached structure with no metallic paths between it and the main building, MAY use a 3 wire feed, but MUST use a grounding electrode with the neutral to ground UNbonded in the sub-panel.
A detached structure with no metallic paths between it and the main building, MAY ALSO use a 4 wire feed, but MAY also use a grounding electrode, with the neutral to ground UNbonded in the sub-panel. It is highly recommended to have a secondary ground rod, and must NOT bond the ground and neutral in the sub-panel when the sub-panel is located in a separate building.
Any detached structure that has an existing non-current carrying metallic path such as water pipes, intercoms, telephone lines, etc. installed between the main structure and the detached structure MUST have an equipment grounding conductor installed with the feeders installed between the two buildings AS WELL as using the water pipe as a ground, AND a supplementary grounding rod, even if an interconnecting metallic water pipe is also connected as ground. Article 250-32-B-1 & 2
It is primarily to prevent telephones, water pipes, intercoms and such from presenting a shock hazard when they are at differing earth potentials, aggrevated by charged atmosphere/earth conditions.
If there is no grounding electrode system serving the detached garage, then you must install a new grounding electrode system as described in Article 250-50. If none of those listed in Article 250-50 is available, then you may use a made electrode as found in Article 250-52. Article 250-50 lists any metal water pipe in direct contact with earth, any rebar in concrete, any grounding rings, and many more as an approved grounding electrode to be combined as a grounding electrode system. If available all of those grounding electrode sources listed in Article 250-50 must be connected together to make the grounding electrode system. Most likely, if you have a metal water pipe run underground between the two buildings, then you have a water pipe in direct contact with earth and that metal water pipe, and any other grounding method listed in Article 250-50 must be connected together to make that grounding electrode system. If that metal water pipe is installed between the two buildings, then you must use that as part of the grounding electrode system but you must also supply a supplemental grounding electrode to back up that water pipe in case that metal water pipe is removed at a later date. Article 250-50-A-2
Remember, if any non current carrying metal connection is existing between that main building, and the detached building, then you must install an equipment grounding conductor between the two buildings, with that feeder and as a part of that feeder installed between the two buildings. Article 250-32-B-1 & 2
Whew...
Greg G.
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You cannot connect the neutral to earth except at the service point. Most often this is done either by using the neutral bar as the earth connection point and as a combined ground bar/neutral bar, or in newer panels via a bonding jumper between the equipment ground bus and the neutral bus in the service panel.
You can have as many ground rods as you want interconnected with each other either directly or through an equipment grounding conductor.
I don't think the phrase "secondary ground" has any defined meaning in the NEC.
A subpanel (another term that I don't recall being defined in the NEC) could have its own ground rod but may or may not have a connection from the ground rod to neutral at that panel. Most often in most residential settings it would not have that connection.

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To summarize or correct many responses. Every utility wire entering the building must connect to same single point earth ground before or as it enters the building. That means AC electric neutral (one type of ground) must connect to earth ground (what the code calls a ground electrode) where it enters the building (called service entrance). This earthing wire could be at meter or at breaker box with the mains (100 amp or 200 amp) circuit breaker. Meter or breaker box is often unique to local utility requirements and typically is a 6 AWG or larger bare copper wire.
All other utilities (phone, cable TV, etc) must also make a less than 20 foot connection to this earth ground.
This earth ground is required for human safety. NEC that requires these earthing connections is only concerned with human safety. However this earthing system must meet or be enhanced to also provide transistor safety. No earth ground is why plug-in protectors do nothing effective - another topic beyond the scope of this discussion.
Water pipe is no longer acceptable for earthing as of 1990. The water pipe must connect to breaker box safety ground (where earth ground, receptacle safety ground wires, AC neutral wire all meet) for human safety reasons - not to be an earth ground connection. Furthermore, no wire may connect to water pipes with the intent of dumping electricity into that pipe. Wire connections to pipes are only to remove electricity from those pipes - a fundamental change in code.
In addition, some jurisdictions require any metallic bathtub be hardwired (again 6 AWG wire) from drain pipe to breaker box safety ground. Further information on safety grounding is summarized by volts500 in the newsgroup alt.home.repair entitled "Grounding Rod Info" on 12 July 2003 at http://tinyurl.com/hkjq
How to find the earth ground? Again, every utility must connect to that earth ground. Follow the wires. All utilities must be earthed to same grounding electrode. If not, then an important electrical upgrade is necessary and may require an electrician. No earth ground means no human protection and no transistor protection.
As noted, remove sub panels - those powered by the mains breaker box - would have safety ground and neutral wire separate and would not connect to earth ground.
Consider geology. For example, if constructed in sandy soil or on a boundary line between different geologies, then consider more earthing than just a few earth ground rods. Well pump protection may also require additional considerations. Again, reasons involve facts beyond this scope.
What will a plug-in ground tester report? Which ground is it testing for? Tester can only detect bad breaker box safety ground connection. It will not report a good safety ground connection nor will it test for any other grounds such as earth ground. Anyone recommending tests using "one of those plug testers into a wall socket" should have known this before posting.
Then another earth ground that is essential to safe home. Note the failures exampled here: http://www.tvtower.com/fpl.html
Happy earthing. Don't get your knees too dirty.
Elmar wrote:

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Insufficient information.... The ground might well be present, but connected in the meter base rather than the main panel. This is common practice - check it before you panic.
Also, if there is an outside main breaker mounted on a ppole with the meter enclosure, the ground could be there.
Jim
Elmar wrote:

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Is there any way of checking for ground indirectly, rather than just physically looking to see if a wire is connected?
Dave

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On Wed, 03 Nov 2004 05:03:40 GMT, "Dave"
your local lowes, HD, Orchard supply, etc. will have fairly inexpensive testers available.. I think the one we carry in our rv was about $20... (lots of rv parks have bad grounding or inverted polarity)

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There probably is a ground. In the main breaker box (but not in any sub-panels), the ground and the neutral are tied together. If you look on the neutral/ground bus bar, you will probably see one fairly large wire (#4, #6, #8 (hopefully no smaller)) that goes into a conduit or out through a cable clamp. That larger wire probably ends up at a good earth ground.
However, it is possible, that the electrician is relying on the utility neutral as a ground. THAT is not a good thing.
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Is there any way to indirectly test to see if there is an adequate ground in a system?
Dave

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On Fri, 05 Nov 2004 01:54:00 GMT, "Dave"

lick it.
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