I'm running 2-2-2-4 from the meter base to a barn and installing a 100 amp load center in the barn. The wire has 2 hots, a neutral and a 4 ga green ground wire. I know to hook the hots to the main breaker and the neutral to the neutral bus, but what do I do with the green wire? There is no place on the meter box to connect it, and the instructions in the GE load center briefly mention disconnecting the neutral bus from the ground bus, but give no instructions on what to do with the ground bus. There is no place on said ground bus to connect a 4 ga wire, and if I did find a way to connect it, where do I connect the other end?
My feeling is that I need a lug to connect the green wire to the ground bus, disconnect it from the neutral bus, and then run the green wire out to a ground rod at the barn. Is this correct? I have been searching online for a week and can't find ANY information on how to do this. The old load center I am replacing had a ground wire from the neutral bus running out to a ground rod. I have read that this is NOT how to do it, so why was it done this way?
Also, why does my 2-2-2-4 cable have a green ground wire running the entire length if I only need a few feet from the load center to the ground rod? Why does my new load center not have provisions for a ground bus connection? There is a part number on a sticker inside the box for a ground bus. Is that what I need?
Sorry for the long post. I am very confused about this
------------------ 1986 SE Aero coupe.
3.4 DOHC swap is complete and running, now just have to finish the rest of the car...
Same bar you put the ground on, but wait till others say the same. that is the way I see those 4 wire connections when I go in to put another bracer anyway.
Not sure about your barn box though
Edit to add, I think I may be wrong so wait for other to post, I am not an electrician.
Steve
------------------ Technology is great when it works, and one big pain in the ass when it doesn't
Detroit iron rules all the rest are just toys.
[This message has been edited by 84fiero123 (edited 06-21-2015).]
I'm running 2-2-2-4 from the meter base to a barn and installing a 100 amp load center in the barn. The wire has 2 hots, a neutral and a 4 ga green ground wire. I know to hook the hots to the main breaker and the neutral to the neutral bus, but what do I do with the green wire? There is no place on the meter box to connect it, and the instructions in the GE load center briefly mention disconnecting the neutral bus from the ground bus, but give no instructions on what to do with the ground bus. There is no place on said ground bus to connect a 4 ga wire, and if I did find a way to connect it, where do I connect the other end?
My feeling is that I need a lug to connect the green wire to the ground bus, disconnect it from the neutral bus, and then run the green wire out to a ground rod at the barn. Is this correct? I have been searching online for a week and can't find ANY information on how to do this. The old load center I am replacing had a ground wire from the neutral bus running out to a ground rod. I have read that this is NOT how to do it, so why was it done this way?
Also, why does my 2-2-2-4 cable have a green ground wire running the entire length if I only need a few feet from the load center to the ground rod? Why does my new load center not have provisions for a ground bus connection? There is a part number on a sticker inside the box for a ground bus. Is that what I need?
Sorry for the long post. I am very confused about this
Does your sub box have a little round bar that that can be used to either tie the ground bus and neutral bus together or to tie ground bus to panel box itself? (bonding strap)
For your sub panel ground, you need one these big lugs to connect your #4 ground wire to. It is fastened in to one of the smaller hole in the ground bus. (this one is on the neutral bus but you get the idea)
Here, they don't ground in the meter box--ground is responsibility of home owner--- Ordinarily, your sub panel's 2-2-2-4 will go in to your meter box, with enough outer insulation stripped off to to expose and allow the ground wire to enter the box, just loop thru the bottom of the box and exit out a hole and tie to your main ground rod. It does mean you wasted the same length of the other 3 wires.
This of course, is not a main meter or feeding house and subpanels, but you get the idea of what your #4 ground wire does in meter base: (if allowed by your local code and utility provider)
Just going by how my house is wired... The ground enters the house as part of the drop from the meter. (I'm not sure if it's grounded at the meter, or carried all the way to the street and grounded at the transformer. We have underground utilities, so it could go either way.) There's two hot legs (with apologies to Rod Stewart), a neutral leg, and a ground. The hot legs go to the buses that feed the breakers. Neutral has its own bus. Ground has its own bus. Many years ago, neutral and ground were tied together. That hasn't been "code" for a long time, though. Thinking since the 1960s or 70s.
It appears that the neutral and ground are tied together at the main panel, but NOT at any sub panel (in another building) fed from a breaker in the main panel. Since I am feeding a main panel directly from the meter (not a sub panel from a breaker in the main panel) I need to treat this like the main panel in the house. The way my place is set up, I have a meter on a pole with hookups to feed up to three structures, each with a main breaker load center. This is the way the house is done and the way the rusty old box in the barn I am rewiring was done.
Out here every outside panel requires a ground rod regardless of a ground wire from previous panel..
Question: What happens, if you lose ground at your main panel? Main panel (200a service) ground is supposed to be able to handle everything the service can throw at it. Outbuilding subpanel service is going to be less than the main 200a tho, and will in almost every case, use smaller wiring including ground wire than what the main dist panel does and what code calls for at that 200A main panel. If you lose your main panel ground, (dry earth, cut ground cable, loose ground rod clamp, corrosion, thief stole the rod and copper ground wire) then your outbuilding sub panel's ground wire and rod just become ground for the entire 200a service. Can that outbuilding's wiring and smaller ground wire handle the 200a service?
[This message has been edited by maryjane (edited 06-22-2015).]
Out here every outside panel requires a ground rod regardless of a ground wire from previous panel..
Same here. And there's a good reason for it. I don't know how far the barn is from the meter, but let's assume it's 100 feet. That means the ground path from the barn would have to travel through 100 feet of wire to get to an earth ground. That is NOT good!
Edit to add: OK, just did some reading up on the national electrical code. Only one panel (the main one next to the meter) should have the neutral and ground buses connected. Every other panel should have the neutral and ground buses separate. Also, every outside panel needs its own earth ground. And all the earth grounds of all the panels must be interconnected. Hope that helps.
[This message has been edited by Blacktree (edited 06-22-2015).]
Originally posted by Blacktree: Edit to add: OK, just did some reading up on the national electrical code. Only one panel (the main one next to the meter) should have the neutral and ground buses connected.
I agree with that and ran into some problems when an outlying shop had neutral and ground bonded together. Caused some havoc with some gcfi tripping.
It does make a difference, whether your outbuilding is fed with a feeder (right off the meter), rather than from a branch (from a big breaker in the main dist panel) . http://ecmweb.com/code-basi...l-conductor-part-3-3
Question: What happens, if you lose ground at your main panel? Main panel (200a service) ground is supposed to be able to handle everything the service can throw at it. Outbuilding subpanel service is going to be less than the main 200a tho, and will in almost every case, use smaller wiring including ground wire than what the main dist panel does and what code calls for at that 200A main panel. If you lose your main panel ground, (dry earth, cut ground cable, loose ground rod clamp, corrosion, thief stole the rod and copper ground wire) then your outbuilding sub panel's ground wire and rod just become ground for the entire 200a service. Can that outbuilding's wiring and smaller ground wire handle the 200a service?
I guess it is a case of better than not having it. I mostly know what I am told and don't actually always know why.
Many people back feed power from solar to their "LOCAL GRID" From different location on a property. In this case running a one size smaller ground isn't allowed here. A single common is also required throughout a system from farthest end all the way to main connect and only connects with main panel ground at main panel even all generator ,inverter or transfer switches. When Disconnect from mainpower grid the common is also switch to first panel on house side of disconnect and it also must have its own ground rod.
From your pole your box get it main common and the main ground rod also to gas and water lines. So there is back up if done correctly. Now they want two ground rods 6 feet apart at main incoming service.
If you ever feel a tingle while in the shower and you are on a well make sure it has it own grounding rod and it is a good clean connection.
BTW. I am not a licensed electrician by trade. I'm general with endorsements and not even that anymore. I'm retired and unbonded. Always look up codes and general practices when you are doing construction you don't know and even if you "know" things change. Even the inspectors are not always right or up to date.
When they built my house in 2008-2009, the electricians ran 2 hots and a neutral to my well. When the inspector cam out, I asked him about it not having a ground wire or rod. "That sub pump's sitting at the bottom of a 130' column of water, if you have problems, an 8' ground rod isn't going to help one bit more than that column of water already provides." The water is in a casing, but the casing screen is open to earth for about 20'.
[This message has been edited by maryjane (edited 06-22-2015).]
Originally posted by Tony Kania: I seem to very often to agree with your building practices and knowledge.
Not being a very smart or educated man has put me in the habit of erring on the side of caution. I also adopted a practice that when in doubt ask the oldest geaser around what he would do.
quote
Originally posted by maryjane:
When they built my house in 2008-2009, the electricians ran 2 hots and a neutral to my well. When the inspector cam out, I asked him about it not having a ground wire or rod. "That sub pump's sitting at the bottom of a 130' column of water, if you have problems, an 8' ground rod isn't going to help one bit more than that column of water already provides." The water is in a casing, but the casing screen is open to earth for about 20'.
Mostly I just know what I'm told but in this case I have first hand experience. HOlding the spray head in the shower would tingle/bite me. I thought the same thing. How is it possible that I am a better ground than a copper rod or a deep ass steel casing? Ground rod had a broken copper line from an over tightened connector so corrosion ruined that ground. The stainless steel pump safety cable went through the well cap and then was attached to a wooden beam. Well cap itself had corrosion. I think in combination it happens that there just might not be enough ground.
Conductivity of water depends on the minerals in it. Also the well cap connection is sometimes insulated from the electrical system because plastic pipe and a nylon safety may be used.
Now I have ground rods everywhere they should be and I grounded the well casing.
[This message has been edited by pokeyfiero (edited 06-22-2015).]
Tying the neutral and ground to the same bus or lug is referred to as 'bonding'. Bonding a panel is typically only permitted in the first means of disconnect, ie, the first panel closest to the meter. A typical main breaker is referred to as a means of disconnect. Hence the main breaker panel is the first means of disconnect. Subsequent panels are grounded using separate lugs. Or bus bars. Look closely around to outer edges of your sub panel and you should see a few pre drilled and tapped screw holes. These are for installing a grounding bus bar. Typically most panels come with a grounding bus kit that would include the lugs and or bus bar and mounting hardware.
Take a look inside the panels that you have. Both the new one you wish to install and the existing ones. Look for a large green screw. This is referred to as the bonding screw. Many times installers will remove the screw completely when not bonding a panel. Sometimes they will leave it but not screw it in. When the screw is not screwed in the panel may not be bonded. Its tricky but I only say it as a precaution as I have seen installers that have left the screw in giving the impression that the panel is bonded when it is indeed not. The screw has to be screwed all the way in, in order for it to bond the panel.
I can only guess as to why a sub panel may have a grounding rod in your installation. My first guess would be that perhaps at one time in the past that point was the service entrance location. I would look for signs of this. Maybe evidence of a weather head once being installed at that location or very large holes that would allow main SEC cable to pass through them. I don't believe ground rods are required at sub panels. However I have no way of knowing your local codes. I would inspect your main service entrance and ensure that both ground rods are present at that location. There should be two of them with a minimum of 6ft between them. Also I would look at your water meter and ensure that it is grounded on both sides. Once before the water meter and once after.
I would install the ground bus in your subpanel and tie all circuits grounds to that. Then at the main panel tie the sub panels ground to the main panels ground and you should be good to go. As long as the required grounds are present at your main panel that is.
How do you plan to run your cable from the main to the sub? Underground would be the optimal route IMO. Then stub up with schedule 80 PVC and LB into the building. Unless you can dig under the baseplate and or sill and penetrate up through.
Work safe, don't trust your glow stick, always meter for hots when in doubt.
Oh yeah and if your using aluminum conductors DO NOT forget the Nolox on all terminations. Or your going to have serious oxidation issues in the near future.
I would install the ground bus in your subpanel and tie all circuits grounds to that. Then at the main panel tie the sub panels ground to the main panels ground and you should be good to go. As long as the required grounds are present at your main panel that is.
he's not going into his main panel--he's feeding the sub from the extra lugs in his main meter base.
I meter everything, and I always shut down the whole place at the pole when I do this type of work.
Thanks for the excellent information. And thank you for reminding me about the Nolox.
It's not a sub panel. It's a main breaker panel just like in the house.
I have 3 structures, all wired off of one meter. Since NONE of the structures are wired from any other boxes (all straight from the meter base), I assume all of them will have the ground bonded to the neutral. The load center I bought (GE 100 amp main breaker) has a green ground screw and very, very poor instructions on what to do with it. It also has no provision for attaching the #4 ground wire to run to the ground rod, so I guess I need to buy that. I assume I need to leave the 2 neutral buses connected, run the green ground screw through the bus the ground wire attaches to and into the box (it threads into the box, or just touches it?), find some sort of lug that will attach to this bus (for the #4 ground wire) and run this wire outside to 2 ground rods, 6' apart. Am I right? I also need to check the house and horse barn to make sure they are done the same.
If I only need to run the ground out to 2 rods, why does the wire I bought have the green ground wire running all 140'? D I pull the whole thing out of the bundle before I bury it, or do I leave it in and run my ground from the box all the way back to the meter pole and put the ground rods there?
This is why I'm confused I have extra wires, missing lugs, a mysterious green screw and sketchy instructions. The internet has been no real help, I have no codes to follow and no inspectors to ask (we are a backward, reclusive society out here )
Next question: How do I properly ground my well pump? It is inside the basement, on the tank, with plastic pipe feeding it. Also, my house has 2 ground rods, but they are 3' apart. Should I move one? How are the grounds run to the rods? Do I run 2 separate lines, or just one out to both?
Sorry for all of the questions. You guys are, as always, a great resource and a huge help.
[This message has been edited by tesmith66 (edited 06-23-2015).]
I meter everything, and I always shut down the whole place at the pole when I do this type of work.
Thanks for the excellent information. And thank you for reminding me about the Nolox.
It's not a sub panel. It's a main breaker panel just like in the house.
I have 3 structures, all wired off of one meter. Since NONE of the structures are wired from any other boxes (all straight from the meter base), I assume all of them will have the ground bonded to the neutral. The load center I bought (GE 100 amp main breaker) has a green ground screw and very, very poor instructions on what to do with it. It also has no provision for attaching the #4 ground wire to run to the ground rod, so I guess I need to buy that. I assume I need to leave the 2 neutral buses connected, run the green ground screw through the bus the ground wire attaches to and into the box (it threads into the box, or just touches it?), find some sort of lug that will attach to this bus (for the #4 ground wire) and run this wire outside to 2 ground rods, 6' apart. Am I right? I also need to check the house and horse barn to make sure they are done the same.
If I only need to run the ground out to 2 rods, why does the wire I bought have the green ground wire running all 140'? D I pull the whole thing out of the bundle before I bury it, or do I leave it in and run my ground from the box all the way back to the meter pole and put the ground rods there?
This is why I'm confused I have extra wires, missing lugs, a mysterious green screw and sketchy instructions. The internet has been no real help, I have no codes to follow and no inspectors to ask (we are a backward, reclusive society out here )
Next question: How do I properly ground my well pump? It is inside the basement, on the tank, with plastic pipe feeding it. Also, my house has 2 ground rods, but they are 3' apart. Should I move one? How are the grounds run to the rods? Do I run 2 separate lines, or just one out to both?
Sorry for all of the questions. You guys are, as always, a great resource and a huge help.
"sub panel" is referring to the fact that it is fed from a common source (your meter base) and isn't the primary panel that sees the most electrical use. The question is, since it isn't fed from a main panel, Is this new panel (and the other outbuilding panels) each considered a/the "first means of disconnect"? Problems 'can' arise when there is more than one bonded neutral--a parallel return path.
Per NEC a feeder wire to an outbuilding will have 4 wires running. When I did my garage I just sunk another ground rod, bonded the lugs on both ends and removed the tap screw. Inspector came out, he was happy with it. If youre running under ground you need to have no more than 60% fill on the conduit. Will post situations and pictures later Source: Industrial maintenance for a living
OK, finally had some time to call the electric company and this is how they said to do it.
At the main panel in the barn:
Connect the 2 hots to the main breaker and the neutral to the neutral bus as usual. Put the green grounding screw in the ground bus, connecting the box to the ground bus. Connect the green ground wire (the 4th wire in the bundle from the meter) to the ground bus. Run a #6 solid copper wire from the ground bus to a ground rod outside of the barn. Leave the ground and neutral buses connected to each other.
At the meter on the pole:
Connect the 2 hots and the neutral to the lugs provided in the meter box. Use a split bolt to connect the green ground wire (that pesky 4th wire) to the solid copper ground wire that goes down the pole into the ground.
They said that all buildings fed directly from the meter are to be wired the same. When I upgrade to 200 amp service, the new meter box will have a lug for the green wire and there will be no confusion. He looked up my account and said that I had an older meter box with no grounding provision. They also said that if I were to feed a subpanel in a different structure from a main panel It should be wired the same EXCEPT remove the bar connecting the neutral and ground buses.
Now that that's all cleared up, I have some work to do.
Thank you, everyone, for your input.
[This message has been edited by tesmith66 (edited 06-23-2015).]
