I want to verify if electricity outlet is grounded. For this I did a test using a bulb connecting it to Phase and Neutral and it lit (to verify if bulb works). Then connected with Phase and Ground and the bulb lit up again. As I still doubted it, I found out where the grounding rod is installed and removed the cable connecting it to the mains (at the grounding rod). Then did the same test and found out that the bulb still lights up. My understanding on this is ... either there is another grounding point or the Neutral is connected to the Ground plug point. Am I correct? How can I verify if the Ground cable is connected to Neutral cable? Thanks

  • If you're in the USA, ground and neutral are usually bonded together in the breaker panel. – The Photon Nov 1 '16 at 20:58
  • The second experiment should have tripped an RCD (GFCI) somewhere, if your protection systems are reasonably up to date. – Brian Drummond Nov 1 '16 at 21:01
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    @ThePhoton I have no idea what definition of electrical engineer you are using, but if you think electrical supply is not engineering and electricians are not engineers, and that they are under "home improvement", you have a rather woefully poor understanding of, um, electrical engineering. – Ian Bland Nov 1 '16 at 21:09
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    @IanBland, also, much like ee.se is not strictly limited to electrical engineering (for example, we occassionally answer questions about optics or manufacturing), diy.se is not strictly limited to questions about home improvement. – The Photon Nov 1 '16 at 21:12
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    @ThePhoton You'll find that both do both, when you get off your high horse. Additionally, I'd be a little surprised if the average questioner here switching LEDs on and off with an Arduino is "making the rules". Furthermore, you might want to ponder that most of the serious electrician work is not going on in homes. I find it amusing to consider that somebody with advanced expertise dealing with thousands of amps and volts is not engineering, but somebody with a 9V battery and a few components on a breadboard apparently is. – Ian Bland Nov 1 '16 at 21:18

In Canada (and probably US) the Neutral and house Ground are connected in the main breaker panel, and that point is connected to a earth ground rod nearby. The power company also connects the Neutral to an earth ground at each distribution transformer. The specifics of Earth ground and Neutral/Ground connections may vary in different jurisdictions.

  • In the U.S. a transformer vault is (in many cases , states, counties) required to have 2 ground rods and copper wire connecting them.+@ Peter Bennett, This is seperate from the home's grounding rod / Ufer ground that are bonded to the neutral & ground buds in the main panel only. – Ed Beal Jun 23 '18 at 18:19

Further to what Peter Bennett says above, here in the UK the two main systems are TNS and TNCS as we call them. TNS is a system in which Earth and Neutral are supplied to the consumer via separate conductors, whereas in TNCS they are combined as one conductor as far as the consumer unit and then separate after it. So it depends what you have. The Earthing rod in your installation is probably there not as the Earth path, but to, er, Earth the earth, which ensures that the local Earth (literally, the earth) is at the same potential as the common Earth of the electrical distribution system.

So it's unlikely that disconnecting the Earth rod will disconnect your Earth from the Neutral, since they are connected either at the incoming service head or at the supply company's transformer.



It is common to see improper residential upgrades even in advanced urban areas like Toronto. done improperly, by immigrant trades people with no professional training, just trying to make a living.

In my previous home the previous owners had contractors upgrade the house with 50 ceiling pot-lights on all floors and when I went to add a 2 way stair/hallway switch, I found they mis-wired it and I had bulb current glowing thru the safety ground in the attic and in wall switch.

You are doing a good test but trace it back to the breaker panel and check earth water mains copper for a ground reference with a Voltmeter.

There is an allowance of 5% of Vac for line voltage on neutral from conduction loss and ground resistance can be as high as 100 Ohms or so at the pole in dry areas in dry weather.

Check your breaker panel to sub-ground water plumbing then check

  • L1 to N
  • L2 to N then
  • N to Gnd in different places with load ON.

A $10 DMM is a good investment if you don't have one.

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