TCI KLR^TM series three phase AC reactors are intended for use as input filters for adjustable speed DC drives and as input or output filters for AC-PWM variable frequency drives.  Drive performance is significantly improved, the drives input rectifier is protected from failure or damage, and drive harmonic demands are tamed with the addition of a K-rated reactor.  KLR reactors act as interface buffers between solid state power circuits and the line or the motor (not unlike the surge protector to your desk-top PC).  All drives, in any application, will benefit when applied with KLR series reactors.