Service Panal Neutral Bar Full

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Old 05-16-06, 05:31 PM
LearningMan
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Question Service Panal Neutral Bar Full

Hello,

Im lost. I have a few questions. Heres what I am doing. I built a garage about 30 feet from the house. Ran 1.25 inch PVC to 100 A panel there. OK on the house I installed a subpanel about 1.5 feet from service panel.
I have 3 #2s and 1 #6 for the ground running from the sub on the house to the panel in the garage. I took out a 20A breaker from the service panel and installed in sub next to it. In the place of the 20A I put a 100A breaker. I also installed a 60A breaker in the sub.
I went from the 100A in the service to the lugs in the sub and then from the 60A breaker in the sub to the panel lubs in the garage. I went from the ground bar in the sub to the ground bar in the garage and from the neutral bar in the sub to the neutral bar in the garage. Im told so far this is correct. Here is my big confusion

---I know the grounds and neutrals go together in the service panel and then split to eaches own in the sub. The problem I have is that in my service panel I have no lug space left to install either the ground or the neutral. I do though have the interior house sub right behind it through the brick. Is it ok to come of the seperate ground and neutral bars on the inside panel to the outside sub panel as long as they will fit through the existing raceway in the brick or is that not right since in that panel they are seperate and not together as in the service panel

---2nd question is about the garage ground. I was told that since I have 4 wires running to the garage. 2 hots, a neutral and a ground and since the ground int he garage is physically attached to the ground bus bar in the other subpanel that I am not supposed to use ground rods because it can create an impedance difference in the ground path and possible create a "ground loop" or something to that nature. Is that right and Ive done the ground ok?

Thanks a lot for the help
 
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Old 05-16-06, 06:24 PM
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Why did you install a sub panel in the house? Do you need it for other purposes?

I prefer not to have a sub running off a sub. I would have run the garage sub off the main panel.

In your main panel you can install another ground/neutral bar. You will then have enough space to attach the ground and neutral wires running to the sub panel.

At each sub panel keep the ground and neutrals separate. Make sure that the neutral bar is NOT bonded to the panel itself, but that the ground is.

Your in house sub panel does not get connected to a ground bar directly. That happens through the ground to the main panel, which should be connected to ground rods and/or the water pipe and/or some other means.

Your in garage sub panel needs a ground bar. The person who told you about ground loops is confused and does not understand the purpose of the ground rods.

Ground rods (either direct rods or a metal water pipe or rebar in concrete are for unusual power surges. The ground connection to the neutral (at the main panel) is for safety for metal appliances and other devices.
 
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Old 05-16-06, 06:41 PM
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Originally Posted by racraft

Ground rods (either direct rods or a metal water pipe or rebar in concrete are for unusual power surges. The ground connection to the neutral (at the main panel) is for safety for metal appliances and other devices.
What??

Is that your final answer?
 
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Old 05-16-06, 06:59 PM
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You sure do like to make friends for someone so new around here.


250.4(A)(5) Effective Ground-Fault Current Path Electrical equipment and wiring and other electrically conductive material likely to become energized shall be installed in a manner that creates a permanent, low-impedance circuit facilitating the operation of the overcurrent device or ground detector for high-impedance grounded systems. It shall be capable of safely carrying the maximum ground-fault current likely to be imposed on it from any point on the wiring system where a ground fault may occur to the electrical supply source. The earth shall not be considered as an effective ground-fault current path.

Ground Rod Does Not Assist in Clearing a Fault
From the above link:
"Note: Metal parts of the electrical system are grounded (connected to the earth) to prevent the destruction of electrical components from superimposed voltage from lightning and voltage transients and to help prevent the build-up of static charges on equipment and material."
 
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Old 05-16-06, 07:04 PM
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Sorry for the confusion. I didnt install a sub in the house. It is the panel for the in house branch circuits. There is a raceway between it and the service panel which is just on the other side of the wall.

Yes, I too would prefer to have the garage running off the main. I did look in the service panel and I dont beleive there is room for another bus bar the way it is made. Its an older unit, probably the original mid 70's. The brand is ITE. It is a one unit type so I cant just replace the bottom half. The meter is built in with 6 quad breaker spots which are all taken up. There is a single bus bar on the left side and no more room for another or mounting holes. (Unless theres a way to mount one on the top of it) The two remaining holes that I thought I was going to be able to use I neglected to notice were the two screws that are securing the bus bar to the panel so I cant use them. So I was thinking I bring the neutral and gound off the inside sub which is about three feet away.

The other thing I might have gotten confused about is the ground. I did buy a ground bar install kit for the sub in the garage. The ground is coming from the sub on the house via a #6 cable and lugged to it. I was referring to whether or not I would still have to drive ground rods and also ti to the ground bar since Im already tied to the ground bar on the house sub.
 

Last edited by LearningMan; 05-16-06 at 07:27 PM.
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Old 05-16-06, 07:09 PM
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Thanks for the reples. Speedy that post that you made with the quote from the NEC site, can you please explain that to me in layman terms. Uh that one really through me. " The earth shall not be considered an effective ground fault". Does that mean that I should or shouldnt use an earth driven ground rod even though I already connected to an earth ground via the ground cable back to the house sub which is tied to the service panel?
 
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Old 05-16-06, 08:08 PM
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Ground rods (either direct rods or a metal water pipe or rebar in concrete are for unusual power surges. The ground connection to the neutral (at the main panel) is for safety for metal appliances and other devices.
How about:

ground rods ,which are for what you state BUT in a more common (as in constant) situation provide a connection to earth (ground) via the gec to provide for a zero potential for any conductor that is bonded to it. If not for this use, a conductor (such as an appliance case) could become energized (via a high impedance path that would restrict current flow via the equipment grounding conductor) and not cause the overcurrent protection to trip BUT if a person who is at 0 potential (via an earth ground path) come in contact with said case, may be exposed to enough voltage and current to kill.

in other words, it causes the metal case to remain at 0 potential.

So you have pointed out one purpose but a more common and unsafe condition is prevented by this system.

Now to the second statement:
the ground connection to the neutral at the panel thing.

Maybe I am misunderstanding what you mean when you say "ground". Many people use this term with many different intents.

now if you mean ground as in earth ground, this obviously would be incorrect. As you pointed out, connecting to earth is not where the safety is.

Now if you meant the equipment grounding conductor being connected to the neutral at the panel, this I can go along with. This would provide the safety intended.

Clarity and precision prevent misunderstandings and mistakes
 
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Old 05-16-06, 08:31 PM
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OK, I guess Im getting more confused by everything. About the ground. Here is what I initially planned. In the service panel on the house the grounds and neutrals go to the same bar. I was going to come off of that bar with the ground to the ground bar I installed in the adjacent subpanel and with the neutral from service panel to the neutral lug in the same adjacent panel. They would then be split as they are supposed to. I was then going to run another wire from that ground bar in that sub to the ground bar I installed in the garage panel and I was going to run the #2 neutral wire from the sub neutral bar to the neutral bar in the garage. Hence they are still seperate. So my question about the grounding was that since they both go back to the service panel and there are no other connections between the house and garage as in a metal water pipe etc, then do I still need a ground rod at the garage or is it fine since its all going back to the ground rod that the service panel is tied to?

The other issue was in the service panel I have found that I do not have anymore room to add either the #2Neutral or the #6Ground. Is it possible to tie those two to the interior sub box (seperatly of course) which is on the other side of the wall that supplies the branch circuits or is there a way to mount another ground/neutral bar on the existing one to give me two more holes to use?
 
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Old 05-16-06, 09:05 PM
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I need to back up.

You removed a 20 amp from the service panel, correct?
What did it feed? What feeds it now?

You installed a 100 amp in place of the 20 and fed the house (sub) panel with it, correct?

What was feeding the house (sub) panel prior to this?

You fed it with #2 and such and is on a 100 amp breaker but what is the house (sub)panel rated at?

The grounds and neutrals need to be connected in whatever panel their associated power comes from. The ground and neutral are bonded in the service panel only. At this panel only, they are bonded to the grounding electrode system.

Depending on how whatever panel you need to attach the neutral and ground is, there is the posibility of buying a double lug to allow the landing of the garage neutral. It is simply a lug with holes for two wires instead of one. Be sue it will phuysically fit and when changing the lug, turn off all power to whatever panel you are installing it in. Getting in circuit with a neutral is just as deadly as grabbing hold of a hot wire.
Additional ground bar kits or even individual lugs can be purchased to attach the garage EGC to.

The ground rod at the garage. I would have to actually look it up in the code book, I have had inspectors require 2 different things. One specifically would not allow a ground rod but wanted EGC back to power source and the other wanted one but no EGC back to source, required the panel equip ground and neut to be bonded (treated as a service panel)

I need to research for a correct answer and for justification for each/either.
 
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Old 05-16-06, 09:16 PM
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Source...Soares grounding and bonding

Grounding - Grounding metal parts to the earth in premises wiring is only useful to provide a path for lightning, shunting high-frequency noise, or reducing static discharge

Bonding - Bonding all metal parts together and then to the system winding (typically to the X0 terminal of a transformer) is done to provide a low-impedance path to the source (system) to facilitate the opening of the circuit-protection device to remove dangerous voltage on metal parts. In addition, bonding the system to metal parts (typically to the X0 terminal of a transformer) stabilizes the system voltage to the metal parts and it provides a zero system reference

Ground Summary

For premises' systems that operate under 600V, grounding (ground rods, water lines, other electrodes"does not":

Assist in clearing a line-to-case fault because of it's high resistance (IEEE 142 - 2.1.4 and 4.1.1)
Establish a "zero system reference"
Reduce shock hazard to a safe value (IEEE 142 - 2.2.8)

Grounding does provide a path to the earth for:

Lightning
Static electricity
High-frequency noise

Bonding Summary
For premises' systems that operate under 600V, bonding the system to metal parts does:

Stabilize the system voltage to referenced metal parts [IEEE 142 - 1.5.2.]
Assist in clearing a line-to-case fault [250.4(A)(3), (4) and (5)]
Establish a "zero system reference" (IEEE 142 - 2.2.8)
 
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Old 05-16-06, 09:44 PM
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We could simplify this a bit, any 4 wire fed subs need a seperate Neutral and Ground bar, a detatched building needs its own ground rod also and if you run out of N spaces in the main panel yoou could add another ground bar mounted to the panel and move some of the equipment grounds from the N bar to the new ground bar to gain spaces. I believe you are allowed to double up equipment grounds under 1 screw to gain some spaces. Its late, was looking for the refrence but didnt find it.
 
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Old 05-17-06, 04:42 AM
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thanks so much for all the heolp everyone. Nap the 20 A I was going to remove is what the water heater is on. I know normally its a 30A but this is a 20 and appears to have been as such for a long time with no problems. I would then have had a 10-2 wire coming from the 20A im moved to the sub back through to the two wires that go to the water heater.

And yes I was going to install a 100A in the service panel where the 20A was. From the 100A then to the main lugs on the sub. In the sub I was going to use a 60A breaker that would then feed the garage. Both the sub and the garage panel are 100A panels. I didnt need that much and went with the 60A to supply it since if there was problem it would trip out there before hitting the 100A in the service.

The house sub that you are asking about, I guess you are talking about the house sub the supplies the branch circuits on the other side of the wall is being suplied via a 70A breaker in ther service if I remember correcly. All of that has been like prob since the house was built.

I will have to check into the double lug idea. I had to buy a lug for the sub panel next to the service for the neutral. Slipped under two screws. The service panel though I guess since its so old has pretty small holes and would be pretty much impossible to put more than one gound wire in each one. The holes are prb about half the size of the ground bar in my sub. So I guess what some of you are saying then is that i can get another smaller ground bar, physically attach it to the metal service panel adjacent to the existing filled up ground/neutral bar and then what? What would I use to bond the two together? A piece of solid copper what size? In this case since I obviously cant remove the service panel, can I drill through it and anchor the added bar through the back of the can into the brick with some small screws and then jump from the filled up bar to the new one? Then start moving some wires. A double lug would be great, but since the hols are so small I dont see how well it would work. Basically this box sucks. LOL
 
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Old 05-17-06, 04:49 AM
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Roger that was good information. Kinda a little techincal though. Im confused as to whether you and Sberry are agreeing that I should or shouldnt use a ground rod at the garage.

Im just trying to do the best I can. I live out in an unincorporated area where they dont do inspections and just want to do it right. Trying to take my time and do it correctly.

So does this: ""Ground Summary
For premises' systems that operate under 600V, grounding (ground rods, water lines, other electrodes"does not": Assist in clearing a line-to-case fault because of it's high resistance (IEEE 142 - 2.1.4 and 4.1.1) Establish a "zero system reference"
Reduce shock hazard to a safe value (IEEE 142 - 2.2.8)"" mean that since this is under 600V circuit mean that I dont need a rod or I do??? I still dont understand if my path to ground is already going back to the service panel 25 feet away and the service panel already has a ground rod why would I need another one??? Simplified pleaseeee
 
  #14  
Old 05-17-06, 05:08 AM
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You need a ground rod at the garage.
 
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Old 05-17-06, 05:13 AM
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Thanks. What size/length? 8' driven to grade?

Just out of curiosity what determines when you need one and when you dont. For example the sub in the house comes off the service and doesnt itself need one. The garage essentially comes off the service, so what makes it need one? Just wondering.
 
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Old 05-17-06, 05:51 AM
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Each structure needs a ground rod (or two). Specically, each building needs a grounding means, of which a ground rod is one of several.

A sub panel in the same building as the main panel does not need one, as the building already has one connected to the main panel.

A sub panel in a separate building needs one, as there is not a ground for the building.
 
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Old 05-17-06, 06:33 AM
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If you are like me, electrically challenged then if often takes a while to understand the why and I have went thru this issue with several guys and even my phone company. They dont understand "why" so they gonna do it like they think they understand it. My phone company tech, his quote is, I just dont understand what a rod does so he dont do it. I see thats not the case with yourself but its really good you want to follow the instructions, the understanding will come with time. I love the codes some people seem to dispise, for me it makes a lot of things simple, I got a guy that works for me at times that stuck his tongue on a battery when he was a baby and when other kids had toy cars in the sandbox he had 8 tracks ripped up, it amazing, I have worked with a lot of people but his ability for electric and trouble shooting is some of the best I have ever seen, I dont even try to keep up. Some people got the mind, this one barely made it thru highschool but compared to my neighbor a master electrician the understanding is light years apart, engineering level in electric and electronics, the rest of us fumble along.
 
  #18  
Old 05-17-06, 06:39 AM
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First I apologoize for getting off track in what you are asking. Bob and sberry are trying to keep things in perspective with DIY and not wonder off on the dissatisfaction by nap with what Bob
stated about ground rods and some of the other electrode options. I dont think it is necessary to explore all the theory about bonding and grounding to satisfy your question.
I've listed two articles to assist you in your understanding of the need for a ground rod.

http://www.selfhelpandmore.com/homew...rage/index.htm

http://www.selfhelpandmore.com/homew...rage/index.htm

First if the building is detached from the building containing the main service panel then you need to pay attention to whether a ground rod is required. It isnt in some cases and is in others. The detached garage article by Mr. Goodrich will have some pictorials that will show when the ground rod is required in a detached garage. The article is somewhat dated (1999 code cycle) but I dont think anything has changed much.
You do not install a ground rod for a sub panel that is installed in the same (attached) structure as the main service panel. You do have to run a four wire feeder to the sub-panel and isolate the neutral bar from the ground bar. The reason for this is to prevent a parallel path for neutral current in the event the neutral would come apart or open. If the egc's of the branch circuits were landed with the neutrals on a common bar then if you lost your neutral connection this bond between the two would allow the neutral current to start flowing on the ground wire of the feeder between the main panel and the sub. This is something that you obviously dont want. You only want this coming together in the main panel where the two are bonded to the grounded conductor (service neutral). The four wire feeder H-H-N-Grd is considered the safest and best wiring method.
There are many 3 wire H-H-N feeders ran to detached structures in this case you would not seperate the neutral and grounds but leave them "married" in the the detached garage sub-panel. Note:....Many juristictions do not allow 3 wire feeders to detached structures only 4 wire.

Yes you need a ground rod at the detached garage it needs to be 5/8" x 8 feet long driven vertically into the ground (use a hammer drill with ground rod chuck if possible). Drive it below ground level about 6 inches. Use an acorn clamp to attach your #6 or #4 grounding electrode conductor from the garage panel grounding bar. I always like to protect the grounding electrode conductor where exposed with non-metallic conduit. #4 isnt required to have protection but I just think it is prudent to do so.

To try to simplify when a ground rod is needed would be to say if the "detached" structure where you are hanging a sub-panel that is going to supply more than one 20 amp branch circuit to that structure then a ground rod is required. If only a 20 or 15 amp circuit is ran to the detached structure then a ground rod isnt required.
If the sub-panel is installed in the same structure with the main service panel then no additional ground rods are required to supplement those already existing as electrodes for the main panel. A four wire feeder is required from the main to the sub-panel with ground and neutral electrically isolated.
 
  #19  
Old 05-17-06, 02:40 PM
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Originally Posted by Roger
Source...Soares grounding and bonding


Ground Summary

For premises' systems that operate under 600V, grounding (ground rods, water lines, other electrodes"does not":

Assist in clearing a line-to-case fault because of it's high resistance (IEEE 142 - 2.1.4 and 4.1.1)
Establish a "zero system reference"
Reduce shock hazard to a safe value (IEEE 142 - 2.2.8)

Grounding does provide a path to the earth for:

Lightning
Static electricity
High-frequency noise

Bonding Summary
For premises' systems that operate under 600V, bonding the system to metal parts does:

Stabilize the system voltage to referenced metal parts [IEEE 142 - 1.5.2.]
Assist in clearing a line-to-case fault [250.4(A)(3), (4) and (5)]
Establish a "zero system reference" (IEEE 142 - 2.2.8)
OK quote from "Electrical Grounding" 4th edition by Ronald P. O'Riley Based on the 1996 NEC
published by Delmar
pg.41:
Responsibility of the grounding electrode

A grounding electrode system can consist of one or more grounding electrodes with specific purposes or responsibilities as part of that system. The grounding electrode's responsibilities are:

1. to maintain good contact with the earth so that all noncurrent-carrying metal parts of the electrical installation, connected to the grounding system, are maintained at ground or zero potential.
2. (paraphrased) the lightning dissipation intent

3. to drain leakage and or static currents, which can be generated or accumulated in or on the system eauipment enclosures, to the ground

-------

another nice side benefit of a grounded system is that it prevents floating voltages. When trying to trouble shoot an ungrounded system, you will read different voltages from each "hot" to earth ground at different points in a system because (there is no neutral )(grounded) conductor and no ground refererence.

Obviously this is contrary to your post of "bonding provides a zero reference"
Unless there is an actual ground reference point, there is no zero reference in a system.

As well you see your post calls for attaching all to XO. well XO also is to be grounded (earth ground). See what happens when you do not ground XO.


------------anyway

to the OP

A ground rod is required (as others have already posted)in your situation.

IF a ground wire (EGC) is brought from the feed, you do NOT bond the neutral and ground in the garage.

If no EGC is run, the EGC and the grounding electrode system and the grounded conductor (neutral) shall be bonded.

NEC 2005 250.32 A and B(1) and B(2)

so since you do have a EGC already, do not bond the neut and EGC in the garage but it does need a grounding electrode system which is bonded to the EGC.
 
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Old 05-17-06, 04:15 PM
LearningMan
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Great info guys. Thanks for the two web site links Roger, Ive already looked over one of them. Lots of info there. Im going to get my ground rob installed and used the noted clamp etc. Might seem like a dumb question but would it be practical to juse a ladder and hammer in with a sledge hammer the rod? Ive seem people say they use a hammer drill, but I dont have one.

Also since that is resolved back to the service panel and my bus bar being full. Can I just buy another bus bar (they dont make my panel anymore so will any brand work) and drill through the back of my service panel and into the brick and then anchor the bus bar vis two small anchor screws??? Also I will have to use a jumper linking the existing ground/neutral bus to the new one right??? Then just simply move some wires around. Would this be the "preferred" method as opposed to trying to find a lug that will fit into the small screws holes to give me two more slots. Thanks a lot.
 
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Old 05-17-06, 09:21 PM
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Originally Posted by nap
quote from "Electrical Grounding" 4th edition by Ronald P. O'Riley Based on the 1996 NEC published by Delmar pg.41:
Responsibility of the grounding electrode

A grounding electrode system can consist of one or more grounding electrodes with specific purposes or responsibilities as part of that system. The grounding electrode's responsibilities are:

1. to maintain good contact with the earth so that all noncurrent-carrying metal parts of the electrical installation, connected to the grounding system, are maintained at ground or zero potential.
This is possible only if the earth has 0 ohm resistance. Reality is something much higher depending on soil composition. I reject your source for its variance from reality.

> 2. (paraphrased) the lightning dissipation intent
Lightning is much higher voltage and resistance is therefore much less a factor. But again, 0 potential is not maintained during a lightning strike. The potential rises above zero. Therefore, I reject your source for its variance from reality.

> 3. to drain leakage and or static currents, which can be generated
> or accumulated in or on the system equipment enclosures, to the ground [earth]

This is nonsense too.
"Static current" is an oxymoron (standing-running). Perhaps the author is a moron.
Leakage or other currents do not "accumulate". Leakage current is not drained to earth in normal operation. The ECG should handle this function.

> another nice side benefit of a grounded system is that it
> prevents floating voltages.

More nonsense.

> When trying to trouble shoot an ungrounded system,
> you will read different voltages from each "hot" to earth
> ground at different points in a system

No, I won't because such a procedure is pointless.


> Obviously this is contrary to your post of "bonding provides a zero reference"

Obviously what you've posted is false.

> Unless there is an actual ground reference point, there is no
> zero reference in a system.

More nonsense.


> As well you see your post calls for attaching all to XO.
> well XO also is to be grounded (earth ground).
> See what happens when you do not ground XO.
Do tell.


Btw, XO is for tic-tac-toe or kissing and hugging.
The 240V/120V midpoint is X0.
 
  #22  
Old 05-17-06, 09:29 PM
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Originally Posted by LearningMan
Can I just buy another bus bar
I probably would. Choose a bar that fits well in your old panel.


> and drill through the back of my service panel and into the brick
> and then anchor the bus bar vis two small anchor screws???

No.

> will I have to use a jumper linking the existing ground/neutral bus
> to the new one right???

No.

> Would this be the "preferred" method as opposed to trying to
> find a lug that will fit into the small screws holes to give me
> two more slots.

Or install some single lugs.

Regardless, the procedure is to drill the enclosure (preferably on a raised area or where there is mortar behind) and tap new holes that fit the machine screw(s) that come(s) with the supplemental ground bar. You do not screw into the brick at all for attachment.
 
  #23  
Old 05-17-06, 09:32 PM
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Originally Posted by LearningMan
that one really threw me. "The earth shall not be considered an effective ground path".
Does that mean that I should or shouldnat use an earth driven ground rod even though I already connected to an earth ground via the ground cable back to the house sub which is tied to the service panel?
No, it says nothing about it.
You still need the rods.

The path the rods provide through the earth is not effective for clearing ground faults.

You also need a solidly connected ("bonded") metallic path, namely, the EGC.
 
  #24  
Old 05-17-06, 09:41 PM
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You also need a solidly connected ("bonded") metallic path, namely, the EGC
Commonally called a ground wire between the panels.
 
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Old 05-17-06, 09:42 PM
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Might seem like a dumb question but would it be practical to juse a ladder and hammer in with a sledge hammer the rod? Ive seem people say they use a hammer drill, but I dont have one.
There are no dumb questions by DIY about electrical might be some dumb answers floating around out there though.

Yes you can use a sledge or T-post driver. If you use a sledge take a three foot or so 2x4 and drill a 1" hole close to one end. Slide the 2x4 over the ground rod and have someone hold the 2x4 to stablize it while you drive it with the sledge.



In order to add a ground bar you must use the factory swaged holes provided in panels back wall if they exist.....looks like bolide has posted an acceptable field modification.


Also I will have to use a jumper linking the existing ground/neutral bus to the new one right???
I have seen this done many times but it is not an acceptable method.
 
  #26  
Old 05-17-06, 10:02 PM
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I believe you are allowed to bolt or screw one bar to another. The best thing is if you can find a threaded hole or bolt it solidly, no sheet metal screws for this though. The code says somewhere that equipment grounding conductors cant be easily disconnected, in other words you couldnt wire nut several together and run a pigtail to the bar unless you used a pernmanant crimp of some sorts, not really something the avg homeowner would do. The intent of this is to have it securely fastened and so that someone wouldnt fool around and inadvertantly leave it disconnected for some reason. Personally in my own installation screwing it down, a jumper with wire as heavy as the largest circuit wouldnt bother me, they allow a crappy strap and or one screw from the factory for bonding.
 
  #27  
Old 05-17-06, 10:47 PM
LearningMan
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Thanks for all the help guys. Im going to go and try and get the ground rod tomorrow and look at what I can find regarding the bus.
There are no preexisint holes to add another bus bar. And I dont have a tap set to tap out screw holes in the box. It is mounted flat to the brick, so theres no recess behind it. Would it really hurt anything to just anchor it through the can and then into the brick.??? The bar would still be on the can it would just be anchored through it.

---------------------------------------
> will I have to use a jumper linking the existing ground/neutral bus
> to the new one right???

>No.
---------------------------------------

Im confused about that. I went outside and looed in it. There is a bar that comes down out from where the meter is and the neutral/ground bus bar is bolted to the the top of it. OK so if I add another ground/neutral bar to the side and I "dont" link them together with a piece of copper, then how is the new one connected to the bar that goes up inside the meter base? Is it only because its screwed to the can and so is the other already there bus bar so you dont need the copper linking them because the can acts as that path???

Kinda cant wait to get my ground rod in now. Thanks
 
  #28  
Old 05-17-06, 11:22 PM
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This is way too complicated and is way beyond the intent here, so this is what I would do "if it was mine" and call it a day. If I was short a couple holes I would take the grounds off of a couple circuits, 15 or 20's and another pc of wire about 6 or 8 inches long and a red wire nut and splice on a pigtail twisting it really tight, so tight it wound the wires all together a couple turns outside the nut so I knew they wouldnt come apart for any reason and stick the wire from the new tail back in the hole and be done, do it a couple times if I needed to, and pound a rod at the garage and hook it to the ground bar with a number 6 wire. Is that the 2 big problems we are talking about here?
 
  #29  
Old 05-17-06, 11:35 PM
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Here is it in as few as words as needed. The thing you want to keep in mind is, there always needs to be a way, a wire from the equipment you have, which from a sub is the 4th wire back to the neutral bar at the main, this is the ground and it is to carry a short circuit. At the main the N and the G are one in the same, they can use the same bar. The short needs to go there in as direct way as possible. A rod in the earth does not do this, it is for other reasons, it needs to be there in detached buildings, the "why" isnt important to you now.
 
  #30  
Old 05-18-06, 04:42 AM
LearningMan
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Sberry thanks for the help. I really do appreciate it. From all of you that have responded. I know that I have asked a lot of questions and can see where from you guy's perspective it needs to come to an end. My current profession is in IT. So naturally no matter what it is I become accustomed to not just doing it but also just 'having' to know the 'whys' and so on but the resoning. Maybe a little more than I need to. But you all have been a tremendous help. Fortunately after the hurricane pretty much blew everything away all along the coast here, it has been either next to impossible to hire someone to do any kind of specialized work due mainly to the sheer number of it and backlog, and also those that seem available jacked up their prices beyond what is normal. Kinda like roofing. Just doesnt seem right you go from 60-75 dollars a square install to over 200. LOL So Im trying to finish up some loose ends. I am blessed though in that I had only minor damage to the house and am able to more easily move on.

If I have another problem I will be sure to come back. Thanks and hope all of you have a good upcoming weekend.
 
  #31  
Old 05-18-06, 06:05 AM
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Originally Posted by LearningMan
how is the new one connected to the bar that goes up inside the meter base? Is it only because its screwed to the can and so is the other bus bar, so you dont need the copper linking them because the can acts as that path???
You are correct!

Don't be surprised. There is a lot of steel, not just a measly wire.
 
  #32  
Old 05-18-06, 01:05 PM
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nap
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Originally Posted by bolide

You also need a solidly connected ("bonded") metallic path, namely, the EGC.
No you don't. In my earlier post I cited NEC '05 where it is acceptable to NOT use an EGC.
 
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