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I live in a 9th floor 1940s-era apartment in a country with no electrical code and no professional licensing for electricians. My 'electrician,' such as he is, is a security guard who does wiring on weekends for extra money. He is obviously not a trained electrician, though he's done a bit of the work over the years. The building is concrete and brick. There's a steel framed elevator down the middle.

My brand new Bosch refrigerator seems to be adding a mild electrical charge to the floor of the kitchen when it's wet, which is somewhat concerning to me. When I plug my laptop into the wall, I am subjected to continuous minor electrical shock while trying to type, which is irritating and concerning. When I touch the TV I get a fairly painful shock. I have a couple of little kids, who I would like to keep from being electrocuted.

My apartment has mostly two-prong plugs (to which I would like to add grounding wire). There is obviously no grounding wire for the building as a whole, or for my apartment's electrical system (which does have a 220v main circuit breaker along with separate breakers for various circuits in the apartment).

My electrician is proposing to drive a 20cm (8in) spike into the concrete of the balcony and ground everything off of that. My opinion is that this won't work. 1) What do you guys think about that? Is there any potential value to his proposal?

2) I am inclined to try to get him to ground everything to the metal cold water supply of the house, which is hopefully, though not provably, metal all the way down. Does that sound like a better idea?

3) I presume not all circuit breakers (meaning mine) are GFCI's. If I add GFCI's to my panel, do I get most of the same protection? And presumably I have to run a third wire from outlets back to the panel in order to get GFCI protection right?

4) Any other things I should be doing/thinking about?

5) Once I get my electrician to implement some changes, how do I test that we've actually got things grounded? I am hoping he has a multimeter. What's the 'for dummies' guide to testing to see if a circuit is grounded?

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    Hello, and welcome to Stack Exchange. My guess is that this is too global a problem for you to solve on your own; trying to ground your apartment might mean having to ground the entire building (and maybe even the entire neighborhood). Out of curiosity, where are you? – Daniel Griscom Dec 16 '16 at 11:27
  • Can you or your "electrician" get their paws on an insulation resistance tester/"Megger"? – ThreePhaseEel Dec 16 '16 at 12:39
  • In the desert here the UFER ground is used provided you connect to the rebar structure in the concrete. You have verified the hot and neutral are wire proper... – spicetraders Dec 16 '16 at 13:51
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    9 stories tall says "not wood" and 1940 says "not concrete". Probably steel framed. There's your ground. Don't even think of driving a ground rod into concrete; might as well drive it into a block of aged cheddar cheese, as neither one conducts electricity. – Harper Dec 16 '16 at 17:19
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    UFER info – spicetraders Dec 16 '16 at 17:32
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Pick an electrical code

Pick an electrical code and follow it. Pick one where your wiring system is normal. If your power is 110/220V split-phase (220V with the neutral center-tapped with 110V on each side), then follow a North American code. If your power is all 220V between neutral and "hot", then follow an EU code.

On split-phase, neutral is serious business

One of the scary things to be found in the North American split-phase system is if you lose a neutral wire. The 120V circuits become imbalanced, and half of them are more than 120V and the other half are less (but they total 240V). And they teeter-totter back and forth as devices blow out until eventually everything smokes. Losing neutral is serious business, and if you can't get reliable neutral from the building owner, you may have to use the outer 240V(220V) lines and manufacture your own 110V service with your own transformer.

This is not an issue if you're supplied single phase 220V from a European style system, if you lose neutral you lose power.

Any shock is deadly shock

People often get "small" shocks and go "well, that's not dangerous". Yes, it is. Remember, electricity needs to complete a circuit. It flows when two things are connected. You made a solid connection with a deadly amount of current from the TV/fridge, however, your connection back to ground/earth wasn't very good, so not much current could flow. Different deal if there's water on the floor or you happen to be touching the sink.

So any appliance that gives you a shock, is a 5-alarm fire and needs to be Dealt With Right NOW before someone else has a "better" connection!

GFCI's are great for shock hazard reduction

A GFCI (RCD in Europe) compares the current flow on the "hot" wire, to the current flow on the "neutral" wire. In normal operation, they are exactly the same; that's what it means to complete a circuit. Current seeks to follow all possible paths, regardless of resistance. If current finds an alternate path (like through you), some of it will go that way, and the GFCI will see that the "hot" flow and the "neutral" flow is not the same, and it will trip. This means your shocking experience won't last for very long.

Note I don't mention ground at all. Like the honey badger, GFCI's don't know or care about ground. Obviously, ground may be part of the fault path, but the GFCI doesn't care about that, it cares that the current is NOT the same on hot and neutral. This means GFCI's do not need ground at all. They are often used to provide safety when a ground is not available - in fact, they provide far better safety when dealing with plastic-chassis equipment, since they are actually looking for electrocution situations.

GFCIs do not provide equipment grounding, however, and sometimes equipment cares about that. Particularly, sensitive electronic equipment which does not like ESD (electro-static discharge, or that zap you get when you shuffle your feet across a carpet then touch a doorknob). That's a ground for a different kind of reason: not personnel protection, but equipment protection. That ground does not need to be tied to the electrical system "neutral". An example of that would be the microcomputer inside a large machine tool connected to 480 3-phase (plain) "delta" power, all 3 wires of which are hot. (let's say that's protected by GFCI so a hot-chassis fault in the motor won't kill the operator). The computer is powered by a small transformer off 2 legs of the 480 delta, which isolates it from everything. The computer needs a ground to give ESD somewhere to go.

Get a better ground than concrete

Concrete does have some conductivity, but I wouldn't rely on it for a long distance. Anyway, "9 storeys tall" means not wood. 1940 probably means steel not concrete. The steel frame is most likely your best source of an equipment ground. You can use reinforcing rod in a building designed for this but they weren't really thinking about that in 1940.

Do Not tie neutral to ground!

Neutral must be tied to ground in exactly one location: the main panel, as in the building's main panel. That's because Neutral Is Not Ground, and there is a voltage difference between neutral and ground. If you tie neutral and ground together in a second location, that voltage difference will result in current flowing, and potentially a surprising amount, since it could involve the whole building's current return! This means ground is handling current on a regular basis, which it's not meant to do. This also breaks any GFCI protection upstream.

You only tie neutral to ground in the main service, which is directly next to the supply transformers. This is necessary since a supply transformer isolates the input power from the output power. It would "float" (at indeterminate voltage from ground) unless you peg it to ground with a ground strap/bond.

Anytime you have current flowing on a neutral-ground bond, that is a very bad thing and needs to be corrected immediately.

  • Better answer than mine. – keshlam Dec 16 '16 at 18:40
  • Thank you! I've read that GFCI's could be an important safety improvement for ungrounded circuits, but never with a clear explanation of WHY or HOW they help improve the situation. Thank you for explaining that hot-to-neutral check. Much appreciated! – Grunthos Dec 18 '16 at 18:12
  • Thank you for a very detailed and useful answer. The electrical system is European style 220v, ie not split-phase. I am particularly grateful to you and Breveleri for underlining that I should not try to ground off of either the water system, or tie neutral to ground elsewhere. I had discovered a seemingly convenient grounding cable that runs down the outside of the building, from some sort of large cellular antenna up on the roof. My immediate thought was to tie the neutral wiring into that cable, thereby grounding everything. Given what you said about current flow, I will avoid that. – Jack B Jan 19 '17 at 22:01
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The symptoms you describe almost certainly arise from a broken or inadequate neutral connection between your apartment and the utility company. Given that you are on the ninth floor and the building is not properly maintained, the problem is probably due to deteriorated wiring in the building.

The only proper and safe fix is to test the neutral connection at the building service panel and then, depending on what that test reveals, either repair the neutral wire between the building service panel and your apartment service panel, or insist that the utility fix the wiring between their grid and the building service panel.

Of course if the building's neutral wire is deteriorated then all the other wires are also, and should all be repaired together.

Codes or no codes, these repairs are the responsibility of the landlord or electric company, not yours. You probably don't even have permission to make repairs in the building.

The kind of grounding you are proposing is called "fault ground" and is not intended to carry current under normal service. It only supplies a voltage reference that the neutral can be compared to by GFCI breakers and other such safety equipment. The fault ground should carry current only under emergency conditions, as when the insulation in an appliance fails, or when a neutral wire breaks.

Concrete is not electrically conductive enough to provide a safe current path for any purpose. The only truly safe fault grounding is through a hefty ground wire all the way to the Earth, or through metal conduit and junction boxes if these have been installed and maintained with the fault ground path in mind.

Metal plumbing can provide an excellent fault ground path. The problem is that while grounding to the pipes can make your electricity safer, it turns the plumbing into a death trap. A combination of electrical fault and pipe corrosion can deliver a lethal shock to all the faucets in the building.

If you install GFCI breakers in your apartment in its current condition, they will trip immediately and stay tripped until the wiring is fixed properly. This will keep you safe from electrocution by denying you any electricity.

If it was my building, I would start at the building service panel. I would test the utility supply neutral wire to insure it is at earth ground voltage. I would examine all connections for corrosion, by disconnecting, cleaning, and reconnecting. Then I would do the same for the apartment service panels. This would probably be enough.

If I could not get adequate service this way, then I would proceed to replace the wires. If I could not fish new wires through in place of the old, I would abandon the old wiring in place and run new wires wherever I could reach. I would not stop until my voltmeter showed no voltage between the apartment service panel neutral bars and a temporary ground reference such as the plumbing.

I would do this not out of love for my tenants but because I do not want to go to jail for negligent homicide. Unless they don't have that in your country either.

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    <Sigh> Downvoters please explain. – A. I. Breveleri Dec 16 '16 at 14:47
  • Not a downvoter, but GFCI breakers have no access to ground, and don't care. (seriously. Check out how a GFCI breaker fits in the panel; it doesn't touch ground anywhere. The neutral strap? That's neutral, neutral is not ground.) GFCI's work by comparing current flow on hot(s) and neutral. GFCI's are quite a good hedge against electrocution in this exact situation. (the only reason GFCI outlets have a ground connection is to serve the receptacles). – Harper Dec 16 '16 at 17:02
  • @Harper: You may be correct, but if OP is getting a tingle from his TV and zaps from his laptop, this represents current that has arrived via the hot wire and is not returning to the outlet via the neutral wire. It is flowing via his feet, the building structure, and the earth back to the utility company. – A. I. Breveleri Dec 16 '16 at 17:48
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    A GFCI will not directly detect that its neutral node has departed from the local ground potential, but when this departure causes current to flow from the neutral to the local ground on the load side of the breaker, the GFCI will detect and respond to the leakage from the circuit as a whole. – A. I. Breveleri Dec 16 '16 at 17:55
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    It would b good to investigate the main panels grounding and neutrals. Africa is no different then many other countries in "scrappers" will find every loose copper bit they can. And it has been reported there of apartments having the building ground wires taken. – spicetraders Dec 16 '16 at 18:31

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