The MV Microprocessor Unit M3 can be used with any of the MV furnaces which come in 6 sizes, ranging from the smallest (KM) size to the extra large (XL) size. Up to different preprogrammed heating cycles can be stored in the unit, and temperatures can be accurately set for up to 4 different steps during a heating cycle. The heating up cycle up can be done in linear steps, with increases in temperature ranging from 1 to 9 degrees Celsius per minute.