This paper studies the manifestation of electrogradient effects in the shape of the voltampere characteristics (VAC) of inhomogeneous conducting sandwich structures of the SSS and MSM types (S stands for n-type semiconductor, and M for metal) during the passage of a current perpendicular to the interfaces between the materials. It is shown that on the ohmic portion of the VAC the Peltier effect in the general case causes the conductivity of the sandwich system to drop. In the region of heating currents the VAC displays segments that are quadratic with respect to the current. The case when the VAC remains linear in the region of heating currents is considered.