THIS DRIVE WILL NOT OPERATE WITHOUT A PLUG-IN HORSEPOWER RESISTOR. Horsepower resistors are available for purchase. KBMD-240D Multi-Drive - NEMA-1 SCR Drive The Model KBMD-240D, also called Multi Drive, is a packaged SCR drive in a NEMA-1 enclosure. It utilizes the KBMM speed control for its electronics. The Multi-Drive 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.