Trying to understand household electrical wiring in India (Neutral vs Earthing vs Grounding)

You can do the best earthing possible at home, and it will not work correctly if the earthing at the transformer is not up to the mark. This is what I heard from a proper electrician.
"Real earthing" involves digging a pit in the ground & bury the main earthing wire inside & is meant to protect the home from lightening strikes, static buildups & power surges. Equipment earthing is a bit different but it shouldn't have any relation with transformer.
 
Heisen is correct in this instance.

I talked a bit about this in #7. The ground/earth/neutral reference is from the utility scaffold on which the transformer is mounted. The earth and neutral bonding is done at that point, and after that the neutral carries the reference to your equipment (utility does not supply the earth but references to it, which is the source of your confusion). The ground is your safety net. The voltage difference exists because of how near/far the transformer is from your location, and how good the earthing resistance is - a function of the quality of the poles and how well the transformer is grounded.

The reason that the live line is dangerous is because it is referenced to earth, and humans can bridge the gap. But it is also the safety net for humans touching the live line in the first place. The danger of not having any reference at all is 'float', where untethered power supplies can drift to a dangerously high level above ground, and cause a current to flow anyway, sort of how lightning works but obviously at a much lower level and lower energy - still sufficient to harm or kill humans.
 
How old is the wiring?
Wiring is old. Last changed 10+ years ago

Do all rooms have their own MCBs?
All rooms have their own MCB
The Tester lighting up is common occurrence in India. It may not be right or OK, I am just stating a fact.
However, if the place where the tester lights up and a reliable earth connection show a Voltage difference of 220V, then for sure there's sho
This is common across all sockets. Also it was a direct connection aka no extension board in between

However, if the place where the tester lights up and a reliable earth connection show a Voltage difference of 220V, then for sure there's short.
As for the Electrician, he did what nearly every common Electrician in India does. Change whatever seems suspicious. No per outlet testing. No isolation or equipment testing. etc.
One of the things to do immediately is remove all Three-Pin EXTENSION boards. Also remove the three-Pin adapters that can connect three electrical appliances. Oftentimes, these are faulty.
Then, Isolate Rooms, and start testing Room to Room, and then Outlet to Outlet. You could find some problematic connections.
  • I tested without 3 pin extn board. And still get the tester to light up
  • I also used a socket tester ( Amicisense Socket Tester ) to get a quick glance of socket status and observe 3 places where earth was open and 2 places where PN was reversed. But the core issue is with 2 pin DC devices leaking current
  • Example
    • 6A socket > Belkin 100W GAN charger > USB C port > USB C to C wire > its metal end > lights up tester + metal surface to ground is 100V
    • This is same socket whose PN , NE , EP readings I have shared .
The ground/earth/neutral reference is from the utility scaffold on which the transformer is mounted. The earth and neutral bonding is done at that point, and after that the neutral carries the reference to your equipment (utility does not supply the earth but references to it, which is the source of your confusion).
If I understand correctly, the N-E bonding is to be carried out by the utility company and where the transformer is placed. ?
Additionally can the consumers bond N - E to any earthing earth source .. let's say before the the PN are attached to the electricity meter ?
 
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I think a diagram will help here:

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The three-phase transformer is not an accurate representation, it's just what the schematic library had to offer.

All currents, including fault currents to earth, will find the path of lowest resistance. Assuming you are touching the appliance (which is assumed to have a live wire shorted to a metal enclosure), the resistance to earth - all the way back to the neutral of the utility transformer output - will need to be lower than your resistance to the same point.
 
First of all lots of thanks @cranky @rsaeon and others ; for your time and efforts for sharing useful info.

All currents, including fault currents to earth, will find the path of lowest resistance. Assuming you are touching the appliance (which is assumed to have a live wire shorted to a metal enclosure), the resistance to earth - all the way back to the neutral of the utility transformer output - will need to be lower than your resistance to the same point.
So what could be the issue here
- Neutral is putting up resistance and thus fault is not going back.
- And NE bond at Transformer is not helping either


And how do we fix this ? Can we bond NE just near home ; which is closer than the transformed ( and before N is attached to meter ) ?
1728469437291.png


Diverting to the earth is much more effective than sending it back to the transformer. The neutral wire is not designed to handle faults, it's only meant to provide a return path for the current that's utilized. The neutral wire can carry faults back to the transformer, but it's not very effective. Earthing acts as an extinguisher for fault currents.
Earthing is bonded to neutral at only one place, and that is the main distribution box and nowhere else.
 
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The bonding you talk about at your home is the earthing rod. Its purpose is to bring the apparent resistance value as close to zero as physically possible. The reduction in resistance from your 3-pin outlet to the main entry board is not sufficient to qualify as a major change, and is half-measures at best.

Multiple ground connections are not an issue, so you can do it from your own flat as well, all the way down into a fresh pit.

Be aware though that in this kind of implementation fault currents will still seek the lowest possible resistance, so there's a rare possibility that other fault currents not generated in your home but sharing the same utility phase, may find their way into that earth and may give rise to strange noise in audio and A/V equipment. We've had this issue with clients who redid their mains wiring with very heavy gauge wire and then complained of noise in their speakers.

Your job is to get every resistor except the last one (YOU) to zero as far as possible, and your body resistance as high as possible - insulating yourself from the floor, for example. this will keep you safe in the case of grounded appliances developing a L-E fault.

This will not solve your tester lighting up or your tingling, FWIW. It will probably lower your N-E voltage to within an acceptable margin, if the utility has done their job properly. For that, you may try reversing the charger polarity to get C4 (shown in one of earlier posts) connected to Neutral instead of Live. It might work, or it might not.
 
This will not solve your tester lighting up or your tingling, FWIW. It will probably lower your N-E voltage to within an acceptable margin, if the utility has done their job properly. For that, you may try reversing the charger polarity to get C4 (shown in one of earlier posts) connected to Neutral instead of Live. It might work, or it might not.
Additionally I will check the charger at some other house/place to rule out any issue with it.
 
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Great thread. Let me add my woes.

Couple of 2-pin DC devices light up the tester bright when touched at metal surface. These include - usb charger, yamaha keyboard and more. Also 100ma RCCB would trip occasionally. To fix, our society electrician got our MCB box + many old rusted MCB changed and removed the RCCB as it used to trip every now and then. He fixed the ground connection. But that did not fix the core issue that we begin with. Understandably he's no good . Raised his hands and said he can't fix it .

Here are few measurements I captured
  • Phase to Neutral - 242 V
  • Phase to Earth - 247 V
  • Neutral to Earth - 9 V
  • When I measure AC between the leaking surface and my body it varies between 40-100V ( bare foot )
    • 100W gan charger
      • It's 65W port measures 110V AC from usb C metal and my body
      • It's 15-20W port measures 20V AC
    • Another USB charger 5V 2A output does not leak anything
  • Sometimes the current pinches, when the surface touches any soft skin like upper arm or just below elbow. But is barely felt when touched with fingers .
Any idea what could be the issue? And how should I proceed to get it fixed.
i have all my usb charger leaking voltage, need to check earthing, its a great great discussion, one of the main important point

people spend more money on costly electrical applicanes but they dont want to spend little more on proper earhign, very sad
its because mainly all local elctrician who do wiring, they dont know much about earthing, and they do not educate home owner
proper earhing cable would save lot of time and future cost
 
Please shed light on the new system of earthing using compound instead of using salt and charcoal. Some use gi rod with chemicals inside. And I read that Copper erodes with the added salt.

Would appreciate your knowledge for a permanent maintenance free earthing for my solar and lightning arrestor diy setup.
 
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