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In my locality there is no neutral wire. Our transmission company runs only 3 wires(all line/phase) and no neutral(4th wire) at all. Out of three, one runs to our houses. I know it sounds incorrect, but this is the case, they are saving the expense on neutral wire.

Here we use earth wire(physicaly connected to earth) in place of neutral . Each house has its own earthing/grounding. So our earth is our neutral. No difference at all. Everything works just fine, no problem at all.

I know that two wires with different potential are required to create a potential difference. I also understand that we can run loads between two phases. But in this case there is only one. Here we are running loads between a phase and a wire physicaly connected to earth.

I know that current flows in closed loop(it goes back to the source). But in this case, there is only one wire coming from sub-station and another is just physicaly grounded, how the circuit even completes? Where is the closed loop?

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marked as duplicate by The Photon, Finbarr, RoyC, Harry Svensson, Lior Bilia Apr 25 '18 at 12:27

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • \$\begingroup\$ en.wikipedia.org/wiki/Three-phase_electric_power \$\endgroup\$ – Eugene Sh. Apr 11 '18 at 20:31
  • \$\begingroup\$ This sounds counter intuitive you can run loads between two phases and so do not require neutral but a single wire does not make sense. Where do you live so I can check details of your local electricity supply. \$\endgroup\$ – Warren Hill Apr 11 '18 at 20:33
  • \$\begingroup\$ @Eugene Sh. Kindly read the "detail" of the question. \$\endgroup\$ – CodeChari Apr 11 '18 at 20:37
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    \$\begingroup\$ Also this Wikpedia article: Single wire earth return \$\endgroup\$ – The Photon Apr 11 '18 at 20:55
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    \$\begingroup\$ Considering the earth as a return path, its resistivity is not so great, but its cross-sectional area is pretty high. \$\endgroup\$ – The Photon Apr 11 '18 at 20:56
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But in this case, there is only one wire coming from sub-station and another is just physicaly grounded, how the circuit even completes? Where is the closed loop?

In my experience, any time a question is asked with a 'just' word used in it, that is where the problem lies. 'Just' tends to be used in the sense of 'with no consequence', or 'this is irrelevant information'.

'and another is just physically grounded'

Re-write that as 'and another is physically grounded'. It is connected to ground. It makes an electrical connection to ground, so that current flows into and out of that connection, with little voltage drop.

The ground connection works to hold the neutral wire at around 0v, approximately the same 0v as your nearby neighbours on different phases, and the same 0v as the generating company, or at least their nearest three phase grounded centre tap transformer. Although a current flow between different earth points will generate a potential difference, when the ground rods are long enough, and the water table is high enough, that voltage difference tends to be low. It's low enough that most of the voltage drop from the phases appears on your loads, rather than on your ground connection.

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