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There are 3 wires in most home appliance I see - 220V, neutral, and Earth. Sometimes when I measure resistance from Earth to certain things in my house, I can see which things have a current path to Earth. What I want to know is, when I touch 220V line, it can shock me if any part of me has a path to Earth. However, is it like a capacitor discharge, or is there a current loop? Because I cannot imagine a loop going back to transformer, as they are isolated, right? Where is the current flowing to?

Willy Wonka
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    Change the "*when I touch 220V line*" to "*if I touch 220V line*" and you will prolong your life by many years. – Harry Svensson Feb 18 '18 at 16:29
  • I get the humor, but content wise pointless answer – Willy Wonka Feb 18 '18 at 16:30
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    That was a comment... not an answer, but If you understand it, it may save your life... – Solar Mike Feb 18 '18 at 16:39
  • Any appliance which is not double-insulated will have an earth or ground wire, and if you measure the resistance to earth from that appliance the resistance should be zero - that's the whole point. – Solar Mike Feb 18 '18 at 16:41
  • Most often on a site built home, the neutral and ground land on the same buss in the box. Mobiles can be an exception, but for the neutral to really be floating from the ground is unlikely. Put a volt meter between ground and neutral. – lakeweb Feb 18 '18 at 16:54
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    Touching 220V AC is highly dangerous. Question should be closed. – Leon Heller Feb 18 '18 at 17:10
  • @user43648: See if my answers to https://electronics.stackexchange.com/questions/211010/why-dont-we-use-neutral-wire-for-to-ground-devices-and-earth-wire-for-closing-t/211020#211020 and https://electronics.stackexchange.com/questions/215868/why-ac-power-plugs-have-three-pins/215870#215870 are of any help. – Transistor Feb 18 '18 at 17:23
  • Reminds me of a problem in my textbook back in college where they asked you about the current that going through the load if the load was a frog. Yeah... I thought it was weird too LOL. –  Feb 18 '18 at 17:53

3 Answers3

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It's normal for the Neutral line to be earthed at the supply transformer. Depending on the wiring system, earth and Neutral may be connected at your home as well.

So if you connect yourself between Live and the earth, then you will be completing a circuit. How badly you get zapped depends on the resistance between you and the earth.

Simon B
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However, is it like a capacitor discharge, or is there a current loop? Because I cannot imagine a loop going back to transformer, as they are isolated, right?

One of the secondary side connections on the transformer is bonded to earth. This then becomes neutral.
Large grounding rods ensure it really is at ground potential.
Your house has a grounding rods as well.

There really is an electrical path when you connect live to earth.

Jeroen3
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If the device is compliant, then it has capacitors from Live to Earth and Neutral to Earth. (Not all capacitors are safe for this, it has to be Y1 and rated for 8kV if I am correct)

They look like this:

Y1 safety capacitor

Community
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DaniFoldi
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    Given the nature and level of the question this answer is as likely to be useful as a bicycle is to a fish. "Compliant" with what, for example? The question is about the live to earth / ground loop. – Transistor Feb 18 '18 at 17:19
  • @Transistor EU, TÜV, etc. all have their regulations, requirements – DaniFoldi Feb 18 '18 at 17:27
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    Sorry, this isn't an answer to the question asked. Downvoting, recommend you delete the answer. – TonyM Feb 18 '18 at 17:37
  • @DaniFoldi: I know and understand that but the OP is unlikely to and it is likely to cause confusion while s/he tries to figure out how it answers the question (when it doesn't). – Transistor Feb 18 '18 at 17:54
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    Maybe you can ask the OP to change his question so that it fits your answer, or just remove this answer. – Daniel P Feb 19 '18 at 00:36
  • @DaniFoldi The reason this isn't really an answer can be seen if the OP question is reduced. Q: I get an electric shock from an appliance, is it due to the main's or capacitors. A: appliances have capacitors.... Yes appliances have input capacitors (EMC related) but it doesn't help explain the closed-circuit he has now completed with his body where he shunts some of the input to earth and back to the nearest utility XFMR –  Feb 19 '18 at 08:39