Soft AC Line Start

This circuit clearly falls under the heading “Why didn’t I think of that earlier?” Virtually everyone who works with electronics has been faced with the need or desire to limit the inrush current of a large load. In the distant past this was achieved by placing a hefty resistor in series with the supply line and using a contactor (or a relay with a bit of additional electronics) to short out the resistor shortly after the load is switched on.