Grounding Rod Info

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Looks ugly. You may want to look for a normal 5 to 8 hole panel grounding bus bar and screw it to that disconnect panel. They can usually accomodate wires up to #4, and some will go even larger. They require a #10 threaded hole in your chassis. If you don't have that, you can get double lugs that bolt to the panel, but you'll need two it doesn't look like they'll fit.

May want to buy a new disconnect. Yours looks old and it may be difficult to now the listings for multiple wires under a screw. Getting compatible bars may even be a problem. I bought a 3R (raintight) Cutler Hammer disconnect that can do up to 125A for about $30 at home depot.

You have more serious problems here (I think volts500 answered some of these questions in a combined reply). You only have 3 wires, and must have 4. It also appears that you have a mix of neutrals and grounds on each bus. Hopefully, the neutrals are on one side and the ground on the other. If not, you need to rearrange them so that is the case. It looks like that big horizontal bar is connecting both your busses together. This needs to come out if you're separating the neutral and ground (unless there is yet another grounding bus that I don't see, but I don't know where it would fit). Then, connect an insulated neutral to the neutral bus and a grounding wire to the grounding bus. I'm not sure if that braided neutral counts as an insulated neutral. You should replace that cable with SER (3 insulated, 1 braided ground), or some other suitable wire/cable type.
Also, look for the bus that has a bonding screw into the cabinet back. This is the bus that must be ground. The other should be insulated and will be the neutral (hopefully, either bar can be bonded depending on which one you put the screw in). It doesn't matter which hole the ground wire uses, because the screws have a minimum and maximum wire limit -- just use one that is correct for your wire (and use the correct bus).
I can't see enough to now how salvagable this is -- you may need to start over.
-- Mark Kent, WA
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Volts500, Mark and Sue,
Thanks to your help and the help of others I now feel I know enough to keep the electrician honest. I've got the soars book on order and I plan to do some of the grunt work myself. I honestly didn't realize this thread would get so involved. It's very kind of you to help out while keeping the focus on my safety. To ease my guilt at having imposed on so much of your time, I can only hope others will get some use out of it as well.
Keeping everything in mind, I'm going to follow Volt's advice for all the grounding. I'm also going to replace the Service Disconnect (as Mark suggested), and rewire the panelboard. Now, this opens up a few more questions. If I had any shame, I would feel too guilty to ask any more, but I guess I'm a bit shameless. If you guys would start giving crappy and vague advice, you really would avoid people like me buggying you so much. ;)
Volts: It appears that the metal housing of the water meter negates the need to jumper it. In this case, I think it would be better to simply attach the grounding clamp as near as possible to the point at which the pipe enters the home. Agreed? (See image) http://www.geocities.com/mydeadpresidents/index.html
As for outgoing circuits, what kind of trouble can be caused by having a mix of neutrals and grounds on each bus? I'm gonna fix it no matter what, but it won't be the first thing I do.
You've seen my Service Disconnect box. Is it common to have a separate service disconnect box as I do? Had it been wired correctly, couldn't I have just used the panelboard which has it's own 100 AMP breaker) and then skip the current Service Disconnect box?
Tell me I have this right. Let's assume I keep the Service Disconnect at 100 AMP but I want to upgrade the box. I would then get a new box (that supports at least 100amps) then add a 100 AMP breaker for the incoming power and then get another 100 AMP breaker for the power outgoing to the panelboard. In other words, because my panelboard has room for the circuits I need and that I forsee needing, I see no reason to try to run circuits from my new Service Disconnect box and therfore, the power should just go straight through. Put another way, I'm not using the panelboard as a subpanel in the traditonal sense. I'm using the panelboard for ALL circuits and the Service Disconnect is really nothing more than a way to kill the main power and provide a lauching point for grouding conductors. Is there anything wrong with this setup?
My main service breaker only allows for 100amps. I've read that a 100 breaker usually means you can go 200 or more, but I've totaled up the amps of the circuits in my panel box and it's around 500! However, in the two years I've lived here, I've never once thrown a breaker. Also, some of the circuits are used seasonally. I've got 60 amps dedicated to the AC, but I also have 160 amps dedicated to space heaters which I almost never use, not even in the winter time (because that same room also has a wood stove). Is it time to upgrade to 200amps?
I regards to power coming into my home (2 hot/1 neutral), how much power is available? I mean, right now, judging by the breaker in my Service Disconnect, I'm utilizing up to 100 AMPs of power. If I wanted to go 200, then can I just upgrade to a breaker and panel that support the extra amps? Or, is there some kind of physical change the Power Co will have to make?
Thanks
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Don't feel guilty -- that what these forums are for. If we get tired of your questions, you'll only get lame (or no) answers.

If it is service equipment, then none as ground and neutral are the same. In a subpanel, the voltage drop across the neutral will raise your ground this same amount (typically 1 to 3 volts). For things that actually go to a true ground, such as audio tuners and cable TV cables, you'll get a current flowing in the shield causing noise, hum, or other interesting behavior.

This seems to be a regional thing. Some areas demand an outside disconnect. Where I live, the disconnects can be inside the house as long as they are very near where the service cables enter. Since your second panel is also outside, you meet the outside disconnect rule. The only other issue would be if your area has a limitation on how far the main disconnect needs to be from the meter. If they have one, it may be short, like 5 feet. The intent here is to minimize the length of unfused service conductors and the amount of structure they will damage should they flame up.

The first panel is still your service disconnect because it has a breaker in it. Additional service rated panels must be grouped (can't be 20 feet across the wall) and there is usually no fusing between them. If your local inspector says its OK, you may be able to replace the 100A disconnect with just a junction box if the existing house circuit panel has a 100A main disconnect. Then run new wires from the meter base to the panel where all your circuits are and use it as a main service rated panel.

Again a local thing. Here, all services must be wired for 200A, but you could put in a 100A breakered panel if you want to. The wires will have to be sized for 200A though. If your service wires are 100A, then you can't increase to 200A without replacing them. Same with your meter base -- is it 100A or 200A? You can put a 200A breakered panel on a 100A service if you've done a load calculation and it indicates you're not exceeding the 100A service. Finally, check with your utility to see how big your transformer is. You'll want at least a 20 KVA for a 200A service, and preferably a 25 or 30 KVA.

100A is available at 240V (24 KVA). Power company may have to increase their wires to you and may have to increase the transformer. You may have to increase the meter base, the service entrance wires and the main panel.
-- Mark Kent, WA
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wrote:

(OK, different subject, I have voided my previous "last question" offer).
If you only have a service panel - as in the meter is on a box and direct wired to a 100A breaker in the service panel - are there rules about separating ground and neutral ? In my box, it's all one bus bar. I also have a subpanel off the main panel - do the rules change when we get into the subpanel ?
Thanks, Bob
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Yes. At the service, where you have the meter and main breaker, this is your Service Disconnect and it is where your "Service" stops. This is the last place that neutral and ground are connected together. If you have another panel in the house, this is a subpanel and it must have a 4 wire feeder and the neutral and ground busses must be isolated. Only the grounding bus may be electrically connected to the panel enclosure in a subpanel.
There is an exception to this for a panels at detached buildings, but there must be no electrically conductive path between the service equipment and the remote panelboards (ecxcept for the service feeder itself). Typical connections that would mandate a 4 wire feeder to a remote building -- grounded phone or CATV wires, or metal water, gas, or oil pipes. I also think that mobile homes must have a 4 wire feeder from the typically yard mounted pole/disconnect.
The idiot that did my house ran a 3-wire feeder to the pool shed (which because its a pool is not allowed), but there is an oil pipe in there and another one in the house. The oil pipe was a parallel neutral back to the panel. Thankfully, this pipe was not loose or arcing in the oil tank!
-- Mark Kent, WA
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wrote:

If the second panel is physically connected to the main panel via a 1.5" coupling, is it still a "sub panel" and is it a source of concern ?
Thanks,
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This coupling is equivalent to the equipment grounding wire, and may even replace the equipment grounding wire if the conduit is hard metal (not flex) and effectively bonded to the service panel or neutral. If these two panels are side by side, then I'm not sure if you're allowed to have it be a second service panel or not. You definitely could if the meter was double lugged and a service conductor went to each. If a breaker in the first panel is feeding the second panel a few inches away, I'm not sure if that forces it to be a subpanel or not...I'm leaning towards it having to be a subpanel, but I can't prove my case.
If this second panel must be a subpanel, then in it you'd need a grounding bus that is bonded to the 1.5" conduit and the neutral bus would have to be insulated from the panel chassis.
-- Mark Kent, WA
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Now we're getting into the what if's and why for's (Although you seem to be grasping the concepts, I'm trying to avoid all of that to keep misunderstandings to a minimum.) Best to jumper the meter and be done with it.......$2 part, 5 min. work, tops. Don't forget to jumper the hot water to the cold water at the water meter.

Can cause all sorts of nasty problems. I think Mark covered that and the rest of it pretty well.
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Most water meters that I'm familiar with use rubber compression or washer type seals. Those big brass nuts, they really don't connect electrically to the tubing to the meter body all that well.
Gary Quality Water Associates
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Mark,

Actually, both my Service Disconnect and Panelboard are inside the house. Outside the house there is only a meter. All in all, having a separate Service Disconnect is fine for now, although I think I'll replace it with the Cutler Hammer box you suggested. Of course the Power Co will have to someone disconnect power for the Service Disconnect to be rewired. How does the Power Co go about shutting down power? Do they have to climb the pole or is there something they can do at the meter?

The meter says something like "200cl 240v 3w" I'll give the Power Co a call and look into it. I'm sure it's not a black and white issue, but if I'm not throwing breakers, is it fair to say I don't really need 200A at this time? I hate to rewire everything only to decide later that I need to upgrade the panelboard too.
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wrote in message

With what you've said now, your panels are OK. Both are service rated panels, and you have two disconnects. One of those disconnects is not really needed and could be removed. Or, perhaps replace it with a 100A transfer switch if you've thought about generator power...
-- Mark Kent, WA
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Mark,

oh no, not another tangent... lol. (generator) I was wrong about the panelboard. It's actually rated at 200A and the breaker is 200, not 100. I'm still considering an upgrade to 200A. Because the panelboard is rated for 200, if I upgrade to 200, I could skip the first disconnect which might be the cost effective way to go. This would mean about a 5 foot run from the outside meter to the panelboard. If I did this, I'm guessing I'd just run all my GEC and other grounds from the ground bus bar. I might check back with you guys on a few things, but I've got enough to get to work now and I think I'll let this thread die.
Oh, but I am still wondering about that ground conductor going from the Service Disconnect to my water meter and pipe (from the inside of the house). Is it bad for the bare conductor to contact armored cable (bx) or metal duct work? Knowing the answer will make a big difference in the amount of work I have to do to run the wire.
Thanks for all your help and advice.
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So your 100A disconnect is required. A single disconnect can not be greater than the size of the service, so a 100A breaker had to be placed in front of the 200A panel main. And right again, if you upgrade to 200, just remove that 100A disconnect box and go straight to the 200A panel you already have.

No, it is not bad. Those things should already be grounded by the circuit that feeds them. Those items touching the GEC won't change anything. If you just don't like doing that, you can run insulated wire, but you'll need to color it green (use tape or paint) where it is exposed. If you're planning on a 200A upgrade at some point, run a #4 copper GEC to the water pipe. Otherwise, you'll need to upsize it when you upgrade the service.
-- Mark Kent, WA
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Volts,
I'll go ahead and jumper that water meter as you said. Regarding the ground wire going from netural bar to water heater over to water meter.... While trying not to make dramtic bends in the conductor, it's going to be almost impossible to prevent the it from contacting the metal ducts and armored cable that run along the ceiling. I suppose I could try to insulate the wire somehow when it gets near the AC, or perhaps I can find some insulated green #4 (afterall, this is being used inside anyway). Does contact with the ducts or AC create a problem? About how much bend can a ground wire take (and still function well)? 135 degrees?
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understood.
In my case it will be MUCH easier if I don't have to worry about the GEC touching the ducts.

That's it for me on this thread. Thanks!
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Sorry, another long post.
Volts 500 wrote:

Mark Wilson wrote:

Right.
Mark Wilson wrote:

If you roll out the new #4 wire on the basement floor from the main disconnect to the water meter, you can slide the wire through the lugs on the two ground clamps for the water heater (clamps not connected to pipes yet). Then connect the #4 to the service disconnect neutral busbar (first box), staple the #4 on its way to the water heater, attach the clamps on the hot and cold water pipes and tighten the lugs....then staple the #4 to the bottom of the floor joists on its way to the water meter. When you get to the water meter, slide on the ground clamps as you did for the water heater. Finito.
Volts500 wrote:

Mark Wilson wrote:

Substitute for what? I seriously doubt that you will find an electrician who won't run the wire on the inside of the basement from the main disconnect to the water meter. The #4 bare wire run to the ground rods will be totally a separate run.......they will be bonded together with the water ground _at_ the neutral busbar in the main service disconnect (first box). Does that answer your question?
Mark Wilson wrote:

No, they will be bonded together as mentioned above, and permitted by code. Actually, it's the prefered method since the water ground is so far away.
Mark Wilson wrote:

I checked them out, thanks, pictures help a _lot_.

OK, that part is wrong, IMO. The cable going from the main disconnect (first box) to the "modern panelboard" should have been a 4 wire cable with two hots, one insulated neutral and one bare equipment grounding conductor. The neutral in the "modern panelboard" must be isolated from ground.........once the neutral is grounded at the main disconnect (first box) it should never be grounded again.
Mark Wilson wrote:

You should have two buses in the "modern panelboard". One bus, the neutral, should be _isolated_ from ground (and have only white circuit wires connected to it). The other bus in the "modern panelboard" is the equipment grounding bus. It should be connected to the panelboard metal enclosure and have all of the bare and green circuit wires connected to it.
Mark Wilson wrote:

This is kinda turning into a mess (that's OK, I kinda figured that it would from the time that you first posted a while back.) Before the electrician gets started ask him how much a new service will cost. IMO, the hourly rate that he is going to charge to fix that mess and the grounding just may come close to the price of a new service. At least tell him that you want a permit pulled and an inspection done for the work that he is going to do so he'll know that he can't take any shortcuts.......and he'll have to fix anything that he knows is wrong. Again, it may be cheaper just to tear it all out and start over.......would only take 4 to 6 hrs. to totally rebuild and properly ground that service (I looked at your pictures). Just keep in mind that rebuilding a service is most likely his bread and butter work......he'll probably have a fixed price that will not reflect an hourly rate. Something to think about anyway.
Volts500 wrote:

Mark Wilson wrote:

The way that I would do it (since it such a long distance) is to drive a ground rod outside where the cable enters the house......connect a #10 from the cable ground block (look for a screw or a lug on it) to the ground rod........then run a #6 (from the ground rod) through the inside of the house and split-bolt it to anywhere on the GEC.....or land it on the main disconnect (first box) neutral busbar. Since you aren't using the cable at this time, if you can get the ground rod in and the #6 to the GEC, if/when the cable gets hooked up, the cable people will be able to do the rest.
Volts500 wrote:

Mark Wilson wrote:

Volts500 wrote:

Mark Wilson wrote:

Something to do I guess. It's my way of relaxing after work too. Plus, while I have my certification and have done my bit as a residential wireman, I've always been a large commercial and industrial electrician. Helping people in this NG helps me stay up with current residential wiring codes, methods, get homeowner feedback, etc., for those times when people ask me to do some residential wiring for them (so much for samaritanism :-). Also, I get a lot of info from other people on unrelated topics in this NG, so it's my way of returning the favor. Of course, a word of thanks or appreciation goes a long way too, and for that, I thank _you_. Also, in your case, you've been jerked around by so many so called "electricians" that I felt you deserved some extra effort.
Volts500 wrote:

Mark Wilson wrote:

Volts500 wrote:

Mark Wilson wrote:

The lightning arrestor is_not_ a replacement for the two ground rods. Since your water ground is so far from the electric service, the two ground rods, IMO, are a_must._ A lightning arrestor is basically useless without a good grounding system.
Volts500 wrote:

If you read that book, you should have no trouble understanding the principles and doing the work yourself.......but still get it inspected, please. The whole job, if you do DIY and pay for a permit and inspection (and including the price of the book) should be about $200. Just remember that I've overkilled this deal a bit in an attempt to avoid confusion and a lot of what ifs and why for's. If you are having trouble driving the ground rods, rent a rotory hammer that has a chuck that is big enough to slip over the ground rod and have at it.
Mark Wilson wrote:

You're welcome. I hope this hasn't become too confusing.
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Correct.
Good! Someone knew what they were doing.

Sorry, I wasn't clear when I said "panel". You must connect the mandatory GEC at the 100A small disconnect box (or other connected service equipment). You may NOT run the mandatory GEC from your modern panel, because it is not part of your service equipment. It sounds like you want to ground from the proper place, which is at the service equipment, which is where neutral and ground are the same wire or bus.
In your other post, you mentioned a water pipe ground. We just went through this in "Ground Rod Questions - summary". To summarize, if you have a metal water pipe that is in contact with the earth for 10 feet or more, you MUST use it as your primary grounding electrode. You must connect to it within 5' from where the water pipe enters the house. This wire must be unspliced from the water pipe to the service equipment neutral lug or wire. If you have a water pipe ground, in most cases you must install a second electrode which is usually a single rod. You shouldn't need two rods, but if you replace your water pipe with plastic, then you do need two. Putting two in now prepares you for the future and improves your grounding electrode system. Additional rods must be at least 6' from any other rods in the same grounding system. Alternatively, if you switch to plastic water service, leave the old pipe buried in the ground and use that as your second electrode (if you can get an unspliced wire to it).
Jumping around the meter means clamping a #4 wire between the input and output sides of the meter. You can't be sure if a meter is conductive, so you must put a jumper around it. This only applies if the meter at your house between the buried water pipe and your inside pipes. My water meter is at the street, and you don't jumper those.
-- Mark Kent, WA
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wrote:

WOuld "MUST" still apply if the proper attachment location to the water pipe is > 35 feet from the panel ? Or would the code then prefer two grounding rods ?
Bob
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Attitude of code is that water pipe is not sufficient as the primary or reliable earth ground connection. A separate ground rod (or something equivalent) is required even if water pipe earthing is available. Other incoming utilities will use that ground rod as central earth ground; not water pipe. Connection to water pipe is supplemental earthing to new installations. Connection to one or multiple earth ground rod (or whatever else you use for the earthing system), all at same point, becomes single point earth ground. Everything earths to multiple ground rods at same point. Even the television aerial should make some connection to that single point earth ground before entering a building even though the aerial itself has a direct connection to a separate ground rod - to fully optimize earthing for surge protection. These exceed code requirements to make a superior protection 'system'.
That connection to water pipe is primarily to remove currents from pipes - for human safety. Same safety reason is why hot water pipes would also be grounded to panel ground. If water pipe is also being used
Code requires a second ground rod if the first does not measure less than 25 ohms. If second rod does not make less than 25 ohms, then a third rod is not required - by code. Code is not optimized for effective surge protection. If earth is so non-conductive as to not supply less than 25 ohms, then a more serious earthing system should be installed such as halo ground, plate electrodes, or Ufer grounding. One rod will make a minimally sufficient earthing connection in most cases. Two rods will make every 'whole house' protector more effective. The most important component in a surge protection 'system' is its earth ground. Earthing and distance of wire to that central earth ground will often be the 'choke point' for system effectiveness. Additional money spent on surge protection often is best spent on enhancing the single point earth ground.
Code does not define how that earth resistance is to be measured. Most locations will get less than 25 ohms with only one ground rod. However, considering how important that earthing system is also for transistor safety, then a second rod is cheap insurance. Utility will install massive grounding networks underneath a substation and still obtain resistance on the order of 2 ohms. The first rod will lower resistance. Every additional rod will provide less improvement.
'nuther Bob wrote:

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