английский => русский Техника Электроника / Электротехника earthing

The mesh voltage "Em" is defined as that particular touch voltage measured between the grounded structure or equipment (and therefore the ground conductor connected to it) and the center of the mesh.


and from wikipedia

"Mesh voltage" is a factor calculated when a grid of grounding conductors is installed. Mesh potential is the difference between the metallic object connected to the grid, and the potential of the soil within the grid. It is significant because a person may be standing inside the grid at a point with a large potential relative to the grid itself.