O/T Service entrance grounding ??

I just bought this house built in 1985. It"s in a residential area, with electric service being underground. My meter pedestal is in the back yard - 75 feet beyond the house. A main breaker is mounted there, and a ground wire runs to a driven ground rod.

Inside the house, the service panel has no main breaker, just the circuit breakers. The neutral buss is not bonded to the metal frame of the service entrance. neither is the ground buss. The ground buss and the neutral buss are not jumpered together. There is no voltage potential between the two busses. Infinite resistance from the ground and neutral to the box.

a) Should each buss be bonded to the box?
b) Should the busses be jumpered together, or does the box serve that purpose?
c) The house is plumbed with copper, but the underground supply line is plastic to the shutoff valve a foot up off the ground (this is south Texas). Should the plumbing lines be explicitly bonded to the electrical ground?

Comments are welcome,too.

Your electrical service will be ok if:
1. You have four wires coming from the meter/outside disconnect- two hot wires, one neutral, and one equipment ground.
2. The neutral will not be bonded to the indoor panel box but will be bonded at the outdoor disconnect.
3. the equipment ground wire should be bonded to the indoor box. It may not have a bonding jumper but may have a bonding screw.
4. Don't know how many circuit breakers you have in the indoor panel, used to be six or less no main breaker was required. This was North Carolina code. May be differant there.
5. The copper water line should be bonded to the equipment ground at the indoor panel. This way if a water heater element shorts out you won't get shocked. Also the gas line needs to be bonded also. DH

There is something really wrong there.
There should be a bond between earth,service neutral and service ground out at the main breaker.
The bond screw should open between the house panel's ground and neutral bars. To prevent neutral current flow on the ground cable.
The panel box should be grounded to the service ground.
The house copper water lines must be bonded to the service ground.
For insurance purposes an electrical inspector should look at this system to find any other monkey wiring.
Is there a metal water well casing nearby?
As there is infinite resistance between the ground and neutral.The ground either doesn't exist, isn't connected or something else equally nasty.

Here is something to add just prior to the home electrical panel. It will provide a local master switch. And a generator connection that isn't mickey mouse.

http://www.reliancecontrols.com/ProductDetail.aspx?TWB2012DR

Did the house pass inspection as someone should have passed the electric system

a}-since in your case the service starts at the main breaker next to the meter base ,the neutral bar in your house panel does not get bonded to the panel box .the grounding bars however, should be mounted right on the box using the factory provided machine screws. no jumpers between the neutral and the ground bar . Also check that a ground wire has been run from your outside disconnect to your inhouse breaker box. Your inhouse copper plumbing should be bonded to ground with a jumper across the water meter if you happen to have one.

There were different rules in 1985 than in 2008+, so some of the things might be ok 'grandfathered in' in your situation. (It would be good for piece of mind, if not the pocketbook, to get everything set up proper - water pipes bonded, main breaker, etc.....).

You have some grounding/bonding issues that don't seem to be safe, and that at least should be fixed.

Typically things are bonded out at the meter at the main switch now, and 4 wires are run to each building - your one building, in this case. There the ground & the neutral should _not_ be bonded.

If only 3 wires came into the house, then the bonding is done differently.

We likely don't know enough of exactly what has been done to suggest fool-proof solutions; but it seems yours is not right at all the way it is, and perhaps someone who knows should look it over & get things right.

I'm just a simple dirt farmer, so don't want to offer exact advice. But something isn't right with nothing being bonded - there are cases they should be bonded one way; and cases they should be bonded the other way. Nothing bonded doesn't seem like it is going to work right at all.

--->Paul

JC, One problem is how your local authority does things and how things may or may not have been different when your service was installed. That being said, here is what is proper around here today........

1. THE NEUTRAL IS BONDED TO THE GROUNDING ELECTRODE (driven rod or rods, buried metallic pipes etc) ONLYYYYYYYY AT ONE LOCATION, WHATS CONSIDERED THE SERVICE ENTRANCE. At the Service Entrance the groundING electrode conductor, often a bare No 4 copper wire, is bonded to the Neutral and it leads from there to the Grounding Electrode which may consisit of one or more driven copper ground rods and buried metallic pipes etc.

It appears your Service Entrance is out at the MAIN BREAKER. Therefore, THERE AND ONLY THERE is the Neutral (a groundED conductor) bonded to the groundING electrode (driven rods or water pipes etc) via the grounding electrode conductor (say a No 4 bare copper wire).

NOTE: If such is the case, at your house THE NEUTRAL IS NOTTTTTTTTTTT BONDED AGAIN. In the house panel (considered a sub panel NOT the Service Entrance) the Neutral Buss and the Safety Equipment Ground Buss ARE NOT TO BE BONDED TOGETHER as if they would be if there was no external main breaker but your house panel was the service entrance.

2. If out at the main breaker the Neutral (a groundED conductor) is bonded to the groundING electrode conductor (which leads to the grounding electrode) THEN YOU HAVE TO RUN FOUR (4) WIRES FROM THE MAIN BREAKER TO THE HOUSE......Namely 2 Hots (L1 & L2) a Neutral (groundED conductor) and the safety equipment groundING conductor.

3. Out at the Main (Service Entrance) the Neutral (a groundED conductor) and the GroundING electrode conductor (often a bare # 4 copper wire to ground rods and water pipes etc i.e. the GroundING electrode) are bonded together AND ONCE MORE DO NOTTTTTTTTTTTTTTTTTTT re bond the Neutral and Equipment Ground Busses together at the sub panel inside your house **********

Got it?????????? At the main breaker bond Neutral to Ground,,,,,,,,,,Run 4 wires to house (2 hots, Neutral, Equipment ground),,,,,,,At the house DO NOT bond the Neutral and ground Busses, i.e DO NOT bond Neutral to ground again

NOTICE I have no idea what your local authority does and how things may have been when your house was wired SO NO WARRANTY THIS IS CORRECT FOR YOU

Im ONLY telling you how its done around here in todays world

John T Long Retired Electrical Engineer and rusty on the latest NEC so NO WARRANTY

Would this happen to be a mobil home? Or in a trailer park? How many breakers?

Leave it alone the Neutral wire is grounded or your system would not work correctly and you would be blowing lights, Tv or what ever.
Walt.

(quoted from post at 23:58:33 12/30/09) Leave it alone the Neutral wire is grounded or your system would not work correctly and you would be blowing lights, Tv or what ever.
Walt.

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ow! I will never cease to be amazed at the things that are said.

Walter, Actually his system can still "work" if the Neutral isnt bonded to good old Mother Earth, but thats NOT a good thing (as you suggest) as it can help to reduce stray currents and/or possibly leave it more prone to damage sensitive electronics if its NOT bonded to earth as it should be and is required.

WE bonded BOTH the HV Primary as well as LV Secondary Neutrals at the pole transformers and again at the service entrances, of course. We wanted the system at one common reference which Mother earth supplied, albeit not perfect.

Fun sparky chat, God Bless and Happy New year

John T

So what's wrong with what I said. If you knew anything about house wiring you would know that The neutral wire goes to ground and is used to get 110 from the 220 input at the main box. If it is not grounded then you get all kinds of odd voltage at the 110 outlets. I lost a bunch of things when my neutral wire came loose on my generator last winter.
Walt

Walt....................what are you talking about? The neutral current does not flow through the bare wire grounding system.
The neutral wire connects at the system service transformers' secondary winding center tap location.
The only reference to ground is the center point of that secondary tap is supposed to be referenced to ground. To prevent the secondary side from floating. And to handle fault current should the transformer secondary fail.
Ground and neutral are DIFFERENT.

This is my main box you will notice that all bare ground and white neutral are connected to the same bars which are connected together on the lower right you will see the number 8 wire going from the bar to ground.
Walt
<a href="http://s77.photobucket.com/albums/j50/WaltDavies/?action=view&current=Housewiring001.jpg" target="_blank"> </a>

I see three code volations in your panel box. DH

The neutral does not go to ground to obtain 120V. The neutral goes to the center tap of the service transformer to provide 120 between the 240V windings.

It appears to me that Walt has a service entrance main breaker panel. A different setup than the original poster.

I see about 5 or more problems besides just the sloppy wiring which some AHJ could gig ya for.

There are 2 white conductor wires on the bottom left going to breakers for 220 circuits that should have black tape on them or colored with a black sharpie to show they are hot wires. There is one white conductor wire to a breaker on the right side as well. At the lower left there is some nm cables coming in that has too much sheath sticking up into the box. On the left side there is a bare copper grounding wire that loops up under the breakers before going to the neutral buss bar that would be dangerously close to the hot buss bars under the breakers.

I also see those added 220 conductors with the aforementioned white wires appear to be 14 guage nm rated at 15 amps. Can't see the size of the breaker, but I'd never run 14 guage for a 220 circuit.

On the right I see yellow twist tie that may or may not be code depending upon what is connected in it. Also on the lower right, there appears to be a black conductor and something else which appears to be a white conductor and a bare copper wire taped together which would not be code at any time.

Maybe not a violation but we don't usually place single breakers above doubles.

Otherwise anything else should be grandfathered in.

Any other opinions?

There is also the massive hole in the lower right side of the panel back. Looks like this was a used panel transplanted into this location.
In addition to the other faults. Just the general sloppy workmanship indicates the work of a jackleg electrician. As an inspector I would have to look at the rest of the electrical system knowing. There must other serious errors elsewhere too.
No insult intended Walt but somebody out there don't care a d*m about you judging the way they wired that panel.

The first disconnect means is considered as the main service panel, in this case being the breaker @ the meter pedistal. This is where the neutral condutor will be connected to a driven ground rod. The panel in the house is a subpanel, which requires the neutral and grouns to be separated. There will be four conductors from the main breaker to the house panel, 2 hot conductors, 1 neutral and 1 ground. The neutral bar will not be bonded to the panel can, but the ground bar will be.

(quoted from post at 12:15:37 01/01/10) The first disconnect means is considered as the main service panel, in this case being the breaker @ the meter pedistal. This is where the neutral condutor will be connected to a driven ground rod. The panel in the house is a subpanel, which requires the neutral and grouns to be separated. There will be four conductors from the main breaker to the house panel, 2 hot conductors, 1 neutral and 1 ground. The neutral bar will not be bonded to the panel can, but the ground bar will be.

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Amen

This is not a mobile home - it's a single story, stick built, on a slab.

There are 4 double pole breakers, 12 single pole breakers in the house box.

Four conductors from the meter pedestal to the house box - ground, neutral, and the 2 hot legs.

I can find NO hole to run a bonding screw through the ground buss to the box.

So, I intend to run a jumper from the ground buss to a spot on the box frame so that the box is not "floating".