An intrinsically safe voltage clamping device includes a regulated rail, a ground rail, and a shunt regulator assembly. The shunt regulator assembly is coupled to both the regulated rail and the ground rail and includes one or more regulating components. The shunt regulator assembly is configured to clamp a voltage applied across the regulated rail and the ground rail to a safety clamp voltage value. The intrinsically safe voltage clamping device also includes a power-sensing component configured to cause one or more limiting components to reduce a power dissipated in the respective regulating components without raising the clamp voltage.