Shock absorbers are a necessity on a rocky, bumpy road for your vehicle's longevity and safe ride. Likewise, an electrical shock absorber (3-phase inductor) can increase the reliability of electronics equipment on 3-phase A.C. lines having noise, line spikes, surges, hard lines, black outs or brown outs etc.

Switching capacitor banks by utility companies can cause high voltage power spikes which can damage electronics on motor drives. Also, induction heating furnaces, electrical smelting, electrical arc welding, close proximity to generators and power mains can all destroy variable speed drives under certain conditions. Arcing from single shoe or roller bar collectors on electrification systems can cause a gradual breakdown of input diode bridges on variable speed drives.

With 3-phase inductors, it is possible to absorb many of these destructive processes in a simple an inexpensive manner. Inductors are small, light and less expensive than alternative protection methods like 100% transformer isolation. The destructive pulses are absorbed in a magnetic field in the device, effectively smoothing out what would have been a large spike of voltage / current.

Selection of the 3-phase line inductor is based on motor full load amperage. On multi motion systems it is necessary to protect the input for each drive separately. A single unit for all motions is not effective unless all motions run simultaneously. In certain conditions when large distances between the variable speed drive (VFD) and the motor are present, an inductor may be used on the drive output side. Inductors can also be used to clean up any electrical noise generated by VFDs going back to the line. If you believe a surge protector is a wise investment for your personal computer hardware, you may want to consider the added security that is available to VFD's with Line Inductors.