A line reactor is an inductor wired in series between a power source and a load. It is generally used in motor drive applications to reduce harmonics, limit inrush current, and protect both the motor and the drive.
Line reactors also filter current waveforms and attenuate noise, which helps eliminate nuisance tripping and increase motor drive efficiency.
When installed on the line side of the drive, line reactors are particularly effective at protecting the drive from overvoltage tripping where impedance might otherwise be too low to counteract voltage spikes. When installed on the load side of the drive, line reactors can manage the peak voltage experienced at motor terminals, protecting motor insulation and extending the life the motor.