Grounding Myths Video on Youtube Question

[Purple]

Hello, Mike Holt, I have a question. On the Grounding Myths Video on Youtube. I have a question on the pictures at 3:43 (the picture with the voltage gradient difference where the man is getting shocked). The VOM reading from the ground contact to the energized pole is 0 Volts. Why is that ? Is it because the energized pole & the ground are now at the same potential of 120V ? I know Mike mentioned that grounding does not get rid of voltage. I just am not sure why the VOM meter is reading 0v at the grounding contact & the energized pole. I know the pole is not at zero volts, the pole is energized at 120V, but the ground contact is connected to earth & is 0V. The VOM meter is reading 0v difference at the energized 120 volt pole & 0v ground contact. Why is there No potential difference reading on the VOM meter between the energized (120v) pole & ground contact ? [FONT=roboto, arial, sans-serif]Also in one of the pics the dog is getting Shocked is that because of the Voltage Gradients being at different potential & the dog is stepping on two different voltage earth gradients ??? [/FONT]
Thank You !!!
Liquid Purple :?

 

[Smart $]

Mike Holt is not a regular participant here on his forum. Perhaps we members can help.


Below is the referenced picture, but a slightly different older version. As best I can tell, it is functionally the same graphic.

 

[Smart $]

...on the pictures at 3:43 (the picture with the voltage gradient difference where the man is getting shocked). The VOM reading from the ground contact to the energized pole is 0 Volts. Why is that ? Is it because the energized pole & the ground are now at the same potential of 120V ? I know Mike mentioned that grounding does not get rid of voltage. I just am not sure why the VOM meter is reading 0v at the grounding contact & the energized pole. I know the pole is not at zero volts, the pole is energized at 120V, but the ground contact is connected to earth & is 0V. The VOM meter is reading 0v difference at the energized 120 volt pole & 0v ground contact. Why is there No potential difference reading on the VOM meter between the energized (120v) pole & ground contact ? ...

Welcome to the forum, [Liquid] Purple. :thumbsup:

Look closely at the picture. Is there a bonding jumper between the pole and the ground rod, where the voltmeter is measuring? What is the resistance between those two points?

 

[Smart $]

Is this the graphic with the dog?

 

[jaggedben]

...The VOM meter is reading 0v difference at the energized 120 volt pole & 0v ground contact. Why is there No potential difference reading on the VOM meter between the energized (120v) pole & ground contact ? ...

Because they are connected by a very low impedance copper wire. Strictly speaking, there is probably a small amount of current flowing and thus a very small voltage drop difference, but it is so insignificant to Mike's point here that he has rounded it down to zero.

Get it out of your head that the earth is zero volts. Every voltage reading is between two points. Two points in the earth can have a voltage reading to each other, and one point in the earth can have different voltage readings to other points in the world, which is what is shown in the picture. What is not shown in the picture, which may a little confusing, is that the white wire is grounded somewhere else in the world nearer to the power source. That's why there's a potential difference between the hot case and the earth. The ground rod shown creates a voltage gradient in the earth because it is (accidentally) connected to the black wire and somewhere else is a ground rod (intentionally)connected to the white wire.