The purpose of the invention is to reduce excessive inrush currents at start-up of power distribution transformers. The addition of a small tertiary winding was installed on a shell type transformer primary winding along with a simple trigger circuit comprised of two commonly available passive components, such as a resistor and a relay. An oscilloscope set for one-shot captures to verify proper operation of the invention. Excessive inrush currents at start-up are repeatedly reduced by >50%.