Hi,

The electrical conductivity dramatically depends on the carbon texture and on its porosity. At similar carbon texture, then the higher the density, the higher the conductivity. A fabric is a highly porous material, whose conductivity also depends on quality and number of contacts between the carbon fibres. The conductivity is thus strongly dependent on the pressure applied during the measurement. In contrast, the substrate is much less porous, maybe not at all, so its conductivity is expected to be much higher than that oif the fabric.

Hope it helps,

Alain