01-07: Cooling Towers and VFD'sBrief description of a variable frequency (PWM) drive. A discussion on the mechanical and electrical advantages, including the energy savings and payback advantages. Power quality issues as it relates to VFD's with reference to a study by EPRI in 1996. Proper wiring methods for power and control wiring, as it relates in the U. S. and foreign countries utilizing CE guidelines.