A President isn't God, can't be everywhere and in every detail. Most of the time I'll be busy into whipping the Bankers.. I'll propose Richard as to be minister of minning, grounding & infrastructure. Laying of the green/yellow safety cord in every home will be free and compulsory, like basic education is..
I'll suggest, also, to elevate the tension to 241V, just to bre 1V over the Brits
So... You're saying that you have 3 wires coming in to your service connection; hot, hot, and neutral (BTW that's called single phase, NOT 2 phase)...
AND all of your branch circuit neutral and grounds are connected only to the neutral coming in...
AND there is no metallic earth connection anywhere around your house.
You claim that your safety earth connection is the neutral current carrying conductor that comes from the HV distribution pad.
I simply cannot see how this is legal or safe. Can anyone explain how this method is provided for in Article 250?
Michael
The ELCB itself is legal; in fact required to be used here (in CA, US) on all circuits serving moist environments etc.
Adding an ELCB to an autotransformer connection as shown in post #1 does not make it safe or legal, or even render it functional.
Really, is anyone here arguing that isolation is not needed???
cheers,
Michael
The only instance I can think of is if his panelboard is a subpanel derived from another main panel board. Like in a multi-family dwelling with multiple meters and main disconnects derived from a single drop. Only the main panelboard (or service disconnect) would have the single point ground to neutral connection. In a subpanel, the ground is required to be separate from the neutral per 250.24(A)(5) to maintain a single point ground system. It really depends where his service disconnect is located relative to the panelboard. The service disconnect (main breaker) can be in another panel separate from the branch circuit panelboard. I've seen main disconnects mounted in a box next to the meter or intergal to the meter panel. But there has to be one metallic earth connection somewhere in the system to meet code.
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Yeah... But that's not the scenario infinia described. He would be seeing a separate isolated neutral buss and a metallic bonded ground buss in the house panel box. There would be a white coded neutral wire and a green coded or bare metal safety ground coming in. I have wired dozens of apartment buildings and condos this way.
I still don't get it... Must be some missing information somewhere
Cheers,
Michael
In every residential installation I have ever done, the safety ground is the responsibility of the utility *customer*. It is required to be in place and correctly wired before the utility company will energize the service.
If that has somehow changed, I would be surprised
Michael
Utility has the obligation to maintain the service up to the masthead for above ground systems and to the meter box for underground systems. The municipality has the responsibility to adopt and enforce codes. Enforcement is performed through the permitting and inspection process. The owner has the obligation to install systems per code and per the laws of the local municipality. The utility has no responsibility in maintaining the ground at the dwelling, only in their distribution system.
Usually. The ground in my house is connected to the neutral buss in the main panelboard and to the street side of the water pipe at the point of entry inside the house. Wire is bare 4 ga. solid copper. There is a 4 ga. jumper that bridges across the water meter to maintain bonding to the water pipes in rest of the house in case the water meter is removed for repair. That's actully happened once as the water co. recently replaced the meter with a smart meter. But don't go adding a ground to your system unless you know what is up with your situation. Get some professional help.
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I intepreted one of infina's posts as saying that there was a ground wire connected to to the ground buss but he didn't see where that wire was connceted to an earth ground. Maybe I read too much into his description. If there is no bare or green coded wire to the panel connected to the ground buss and if there is truely no other earth connection, then his ground would be floating and not per code. Not a good thing.
Gentlemen:
Wow!...Almost seems like its' the Star grounding vs. Buss bar debate...doesn't it?
Upon further inspection..I have a total of four breakers on the line coming into our house..?
The line drops from the overhead into Two breakers, split between the Duplexs' one to ours & one to the neighbors, onto "our" breaker on the other side of the wall...Put there by the utility(Neat install & sealed). Immediately at the side another breaker(The hack job). Then run into the house & another breaker on the wall.
I will be running my own Earth as I don't trust ANY of the wiring here.
______________________________________________________Rick...
Wow!...Almost seems like its' the Star grounding vs. Buss bar debate...doesn't it?
Upon further inspection..I have a total of four breakers on the line coming into our house..?
The line drops from the overhead into Two breakers, split between the Duplexs' one to ours & one to the neighbors, onto "our" breaker on the other side of the wall...Put there by the utility(Neat install & sealed). Immediately at the side another breaker(The hack job). Then run into the house & another breaker on the wall.
I will be running my own Earth as I don't trust ANY of the wiring here.
______________________________________________________Rick...
Attachments
infinia:
What type of sheath, if any, on this cable? Is it an armoured cable or just USE/SE (gray jacket). National Code is most clear, and has been for at least 50 years, on bonding standards for service entrance. California Code has not taken exception to the NEC 250 section.
The utility always (not usually) bonds their neutral at the pole (or padmount, or vault) transformer. The ground is typically not carried through from transformer to service entrance, however- just the phase and neutral conductors (google messenger supported wiring). A separate rod system (there are many options) is required to generate a unique ground grid for the house. Most of us recognize this as two ground rods, though only one is required when under 25 ohms (electricians can't measure rod resistance, so they by default install two). Water main, if available, is to be bonded to this unique grid, though there are some changes to this requirement that are outside the scope of this thread.
Point being you will not have a common ground with the utility, but you do absolutely need a ground.
There is an additional required (not optional) bond at the customer's service entrance. This bond might be as simple as a green screw driven from the neutral bus into the back of the panel, but it needs to be there. Sometimes there is an additional bond in the meter socket, but that's maintained by the utility.
Now if your 200A panel is not considered service entrance, as might be the case for multi-family dwellings, you will not have the neutral bonded at your panel. But you still need a separate ground conductor going back to a grid, wherever it may be. It is possible an armoured jacket is being used for your ground. There must be something; the use of the conduit for an approved ground has disappeared from the Code quite a while back, and I doubt in a newer home you refer to that any conduit is being used at all.
What type of sheath, if any, on this cable? Is it an armoured cable or just USE/SE (gray jacket). National Code is most clear, and has been for at least 50 years, on bonding standards for service entrance. California Code has not taken exception to the NEC 250 section.
The utility always (not usually) bonds their neutral at the pole (or padmount, or vault) transformer. The ground is typically not carried through from transformer to service entrance, however- just the phase and neutral conductors (google messenger supported wiring). A separate rod system (there are many options) is required to generate a unique ground grid for the house. Most of us recognize this as two ground rods, though only one is required when under 25 ohms (electricians can't measure rod resistance, so they by default install two). Water main, if available, is to be bonded to this unique grid, though there are some changes to this requirement that are outside the scope of this thread.
Point being you will not have a common ground with the utility, but you do absolutely need a ground.
There is an additional required (not optional) bond at the customer's service entrance. This bond might be as simple as a green screw driven from the neutral bus into the back of the panel, but it needs to be there. Sometimes there is an additional bond in the meter socket, but that's maintained by the utility.
Now if your 200A panel is not considered service entrance, as might be the case for multi-family dwellings, you will not have the neutral bonded at your panel. But you still need a separate ground conductor going back to a grid, wherever it may be. It is possible an armoured jacket is being used for your ground. There must be something; the use of the conduit for an approved ground has disappeared from the Code quite a while back, and I doubt in a newer home you refer to that any conduit is being used at all.
Seems like all of your neighbors would be in the same situation? Do you have a neighborhood association where you could perhaps raise this issue? Presumably someone has or can get the information you need, presumably worst case the local electrical inspector could shed some light on this issue.
Ultimately I would expect that if the work was not done to code the contractor might still be liable for it if it was not compliant at the time the work was performed?
As far as my comments go about the gas main or anything else, I'm not an electrician and can only quote from Nema (inaccurately at that), but where I live gas lines are deliberately by code not bonded to the rest of the house grounds, and the piping entering the house is not electrically isolated from the internal gas lines or the appliances they are connected to either. In ground gas line around here by code is only black iron.
As pointed out you will need professional assistance if there really is an issue to be resolved. I hope there isn't, but good luck!
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Hi Infinia,
Ouch.. Sorry on the developer issue. As far as doing measurements are concerned I really think you ought to call in a professional at this point, how to interpret the result is the issue and the consequences could be pretty serious..(I'm not really sure how you could make a determination based on measuring between the neutral/safety bus bar in your panel and a water pipe ground whether or not this is safe or to code. I'm sure I couldn't - I need the physical evidence.) I'd find a top notch electrician to verify your suspicions and ask him if necessary to install a set of grounding rods & bond the cold water system to the ground system with the requisite inspection afterwards - that would definitely put this issue to rest.
I would also ask a few of your neighbors if they have any reason to suspect that they might have the same problem. (You probably don't want their ground currents circulating through your mains neutral connection if you turn out to be the only good ground in the neighborhood..)
Hopefully Michael Koster will weigh in with some further thoughts, I would guess he is a very experienced licensed electrician, and if not, nothing he says in any way contradicts my limited knowledge. (I've done some major wiring that passed inspection in the past, but I am not an expert in any sense.)
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