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So after reading about earthing and earthing mats, I decided to make myself a very basic one for cheap to test the concept before jumping in with purchasing more sophisticated products.

Here's what I have:

  • A grounding plug wired on the ground pin with a 2m speaker cable. (I split the 2-wire cable and only used one wire. ).
  • The other end is connected to an alligator clip, which is clipped to my basic earthing mat.
  • The earthing mat is a cardboard sheet with aluminum foil taped on one side with aluminum tape. The clip is connected to this tape.

Here's how I measured my body voltage and the associated readings:

  • Insert black-prong of multimeter into a separate outlet ground. Other end connected to COM port on multimeter.
  • Put multimeter in V AC mode. Mine only has 200V and 500V, so I picked 200V.
  • Hold red-prong of multimeter in hand. Reading is 00.0 but briefly reads up to 00.2V (200mV) if I move around.
  • Now, when I ground myself by stepping onto the earthing mat, the reading jumps to 00.5 (500mV) and stays there.
  • A second person in the house read 00.6 (600mV).

This didn't make any sense to me. It appears that my body is drawing positive voltage either from ground or from the earthing 'mat'.

I also tried connecting the black-prong of the multimeter to the alligator-clip on the earthing mat and also got the same result.

Can someone please explain what is going on? Did I make a poor earthing mat or is the earthing "mat" acting as an antenna and defeating the very purpose of grounding?

How is it that all other DIY earthers get the exactly opposite result?

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  • \$\begingroup\$ Welcome to EE.SE. \$\endgroup\$ – Sparky256 May 8 at 3:11
  • \$\begingroup\$ How far apart are the outlet used to ground the mat and the outlet used to connect the black prong of the meter? Are they two outlets in the same box in the wall, or across the room from each other? \$\endgroup\$ – The Photon May 8 at 3:41
  • \$\begingroup\$ The two grounds are about 5 feet apart in different boxes, same room. \$\endgroup\$ – urover May 8 at 11:39
  • \$\begingroup\$ Thank you Sparky256. I'm not electrically inclined, so many thanks to you all for helping me out here! \$\endgroup\$ – urover May 8 at 11:40

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