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Discussion Starter · #1 ·
I live in the US but have recently been visiting my parents' home in India.

I have noticed that
- I get a tingling /buzz if I touch the metal chassis of my iPhone5 while it is connected to the 220V mains and is charging.
- my Dad received a shock from one of the switches while trying to turn on a light.
- I think I feel a bit of a tingle from my cell phones and laptops even when they are not connected/ plugged in to charge. This tingling is very minor and almost feels like static electricity in my fingers, arms or even legs.

I've generally been wearing rubber slippers around the house so am usually not grounded.

The house was constructed about 20+ years ago, and grounding / earthing is not always great in India nor maintained up to US / UK standards. We had an electrician come in yesterday and he tested all the sockets / outlets in the house with a tester and gave them a clear bill of health. His tester was one of those that only show a bright light if there is grounding and not actually show an Amp / Voltage reading.

I have a few questions:

(1) Could the grounding / earthing pit have drifted over time to something other than zero potential, which is why there is some current leakage in the appliances? The simple tester is not picking that up since there is still a large potential difference between the "hot" / live wire and the ground, but ground is not at true zero?

(2) Is it possible for my phone and laptop to be delivering little tingles to me even when they are not plugged in or am I imagining things?

(3) Can there be static electricity build-up in the house for whatever reason that's transferring to the metal appliances?

(4) Is it even possible for me to get any kind of shock while wearing rubber slippers which should be insulating me from being the ground / earth connection?

Afraid for our safety, and appreciate all help. Thanks!
 

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What earthing system does the home have TT, TN-C-S, TN-S?


It could be many things. Its possible you have a fault somewhere. IS everything in the home shocking or just a few items?

Other then that if plastic items are giving you a shock that would most likely mean static electricity.
 

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kidding me, like he would know that……….I didn't know that :- )

http://electrical-engineering-porta...f-earthing-arrangements-tnc-tn-s-tnc-s-and-tt

Common way of describing the various earthing systems in India. Those terms arent used in the US, some of them aren't even legal here hence not well known.


Lastly there is the TT system which uses mother earth as part of the earth return.
If the OP has this system it better have functioning and correctly installed RCDs (GFCIs) with low ground rod resistance to pass at least a hundred milli amps. If not it could explain the shocking metal.
 

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Residual current devices with small imbalance current tripping (ca. 5 ma) on both current carrying conductors (with 240 volts between them) will provide near perfect protection from electrocution although it will still be possible to feel tingling. These would be in the form of receptacles (wall plugs) or panel breakers. These would be in addition to RCDs associated with grounding rods.

Equipment grounding conductors (earthing wires) are not needed to have this protection.

Encountering static electricity would give you a momentary tingle or pricking sensation. A continuous tingle indicates electrical leakage if not actual contact with an energized object.

Yes it is possible to feel a tingle from current leakage even if you are wearing rubber soled shoes. There is some capacitance between your feet and the surface you are standing on. Depending on the material of your shoe soles and its thickness the smaller the capacitance the less leakage current flows through your body. (Direct current does not flow as a result of capacitance; the higher the AC frequency the greater the current flow all other things being equal.)
 

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Discussion Starter · #7 ·
Unfortunately, as ritelec suspected, I don't know what type of earthing system the house has. All I know is that there is a charcoal earthing pit behind the house that the earth wires are grounded to, and that the pit hasn't been maintained in about 20 years

For an immediate safety concern, can someone tell me if I'm at least safe touching appliances while they are not plugged in to the outlet? E.g. after a laptop or phone has charged, and I've disconnected it (using rubber gloves), they should be safe to use, right? I feel like I might still be getting tiny tingles or pricks from them, but am I imagining that?

Thanks
 

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After you unplug something that is not physically damaged (such as exposing battery terminals) it is safe to touch with bare hands.

Modern lights, equipment, appliances, house current operated electric toys, etc. should not have exposed metal connected to any of the current carrying conductors even if one conductor is referred to as neutral.

Some older appliances, notably clothes dryers, have the frame connected to a current carrying neutral. If the neutral is not properly earthed then it is possible to get a shock.

The earthing in your parents' home will remain unknown until it is inspected carefully and repaired. It is possible that there is a metal plate in the earthing pit and the wire (grounding electrode conductor) going to the breaker panel neutral bus bar has rusted out somewhere along its length. If that is the case a repair is needed before you can draw any more conclusions. To just get started in the direction of U.S. or U.K. earthing standards you would upgrade this to #6 copper if not already.
 

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Lost track of what was changed and 30 minutes of editing has expired so for my expediencey I reposted the latest version here.

After you unplug something that is not physically damaged (such as exposing battery terminals) it is safe to touch with bare hands.

Modern lights, equipment, appliances, house current operated electric toys, etc. should not have exposed metal connected to any of the current carrying conductors even if one conductor is referred to as neutral.

Some older appliances, notably clothes dryers, have the frame connected to a current carrying neutral. If the neutral is not properly earthed then it is possible to get a shock.

The earthing in your parents' home will remain unknown until it is inspected carefully and repaired. It is possible that there is a metal plate in the earthing pit and the wire (grounding electrode conductor) going to the breaker panel neutral terminal strip (bus bar) has rusted out somewhere along its length. If that is the case a repair is needed before you can draw any more conclusions. To just get started in the direction of U.S. or U.K. earthing standards you would upgrade this to #6 copper if not already.

With some practice and skill you may be able to identify a network of conductors up on the utility poles that is earthed, namely connected to wires on some of the poles coming down to earthing rods. You may see that one of the feed wires (service wires) coming to the house is connected to that network, and connected to the neutral bus bar in the house breaker panel. Proper earthing of the panel is completed by the grounding electrode conductor from the panel to the plate in the earthing pit and/or another ground rod.
 
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