THIS DRIVE WILL NOT OPERATE WITHOUT A PLUG-IN HORSEPOWER RESISTOR. Horsepower resistors are available for purchase from our Amazon store. KBMD-240D Multi-Drive - NEMA-1 SCR Drive The Model KBMD-240D, also called Multi-DriveTM, is a packaged SCR drive in a NEMA-1 enclosure. It utilizes the KBMMTM speed control for its electronics. The Multi-DriveTM is rugged and compact in size. It handles both 115 and 230VAC line inputs by setting the built-in Dual Voltage Switch. In addition, the single model can be used on a wide range of motor horsepower by inserting the appropriate Plug-in Horsepower Resistor®. The Auxiliary Heat sink (optional) increases the rating of the basic unit. An optional Forward-Brake-Reverse Switch Kit is also available.