As VFDs have evolved over the years, new unique challenges have presented themselves to those who are specifying and designing them along with the motors they are controlling. These challenges have come about for a variety of reasons. First, the motors being controlled years ago were overdesigned and less efficient than those we have today. VFDs did not have the technology to control as much so the motors had to be engineered more precisely and effectively. Because they were so overdesigned, the older motors were . . .