AC Line/Load Reactors

An AC line/load reactor is an inductive device installed in series with either the input (line side) or output (load side) of variable frequency drives (VFDs) or other power electronic equipment. It limits current surges, reduces harmonic distortion, and protects sensitive components from transients. Rex Power Magnetics AC reactors improve power quality and extend equipment life by mitigating voltage spikes, reducing current distortion, and filtering unwanted noise from the electrical system.

Reactors limit harmonic distortion, reduce motor noise, and improve current waveform quality. They also help achieve compliance with IEEE 519 harmonic distortion limits. Line reactors reduce the risk of nuisance drive tripping due to voltage spikes or sags, while load reactors protect motor insulation from reflected wave voltages. The result is smoother operation, lower maintenance, and extended equipment life for both VFDs and motors.

Yes. Rex Power Magnetics specializes in custom line and load reactors tailored to specific drive, voltage, or harmonic requirements. Options include custom inductance values, current ratings, terminal configurations, and enclosure types. Engineering teams perform system-level analysis to optimize performance for harmonic mitigation, voltage waveform improvement, and equipment protection. Each custom reactor is fully tested and certified to ensure compliance and long-term operational reliability.

Each reactor uses high-grade electrical steel laminations and precision-wound copper or aluminum conductors. The core and coils are dipped in polyester resin to improve mechanical rigidity, insulation integrity, and moisture resistance. This coating reduces vibration and noise while protecting against environmental contaminants. Reactors are air-cooled and designed for continuous-duty service, with thermal and mechanical bracing that ensures stability under short-circuit and harmonic loading conditions.

AC reactors are rated by their inductance (in millihenries) or percentage impedance (%Z) at a given current. Common ratings are 3% or 5% impedance, which determine the degree of harmonic reduction and transient suppression. Rex Power Magnetics engineers select core materials and conductor sizes to maintain linear performance under full-load current without core saturation. Custom ratings and tolerances can be provided for unique system conditions or harmonic profiles.

AC reactors are used in drive systems, harmonic filters, renewable energy installations, and industrial power distribution networks. Common applications include pumps, conveyors, HVAC systems, compressors, and automated manufacturing lines. They are also used in systems with frequent switching or long motor lead lengths where voltage reflections or high dV/dt may occur. Rex Power Magnetics reactors are suitable for industrial, commercial, and OEM applications requiring enhanced electrical protection and power quality.

Reactors protect both the drive and the motor from electrical stress. They dampen voltage transients, filter switching harmonics, and reduce the effect of power line disturbances on drive operation. When installed on the line side, they prevent nuisance tripping and extend VFD lifespan. On the load side, they reduce cable stress, protect motor insulation, and minimize electromagnetic interference. Rex Power Magnetics reactors help ensure stable and reliable operation in harmonic-rich environments.