Current-carrying bolted joints are often used for power transmission between electrical components of vehicle electrical systems and between electrical components in the field of electrical energy technology. In order to ensure the long-term stability of such joints, there must, among other things, be a minimum surface pressure between the clamping parts. If the surface pressure is too low, the contact resistance can increase significantly as a result of dynamic environmental loads. To determine this minimum surface pressure, more precise knowledge of the mechanically load-bearing contact surface or the equivalent cross-section of the bolted joint is necessary. There is already a model for determining the equivalent cross-section of a bolted joint. The suitability of this model for describing the contact behavior of current-carrying bolted joint was checked and confirmed in earlier investigations on bolted joints made of conductors with a thickness of 10 mm. In this article, the suitability of this equivalent cross-section model for the contact behavior of bolted joint made of conductors with small thickness (1…5) mm is examined and its transferability to large conductor cross-sections is checked. Based on this equivalent cross-sectional model, the minimum surface pressure of selected contact pairs is determined, taking dynamic environmental loads into account. Using these parameters and the model for determining the equivalent cross-section, the minimum assembly preload force of similar connection geometries can be calculated. This ensures the long-term stability of current-carrying screw connections.