Harmonic Filter Reactors

MSI Harmonic Filter ReactorHarmonic Filter Reactors

Harmonic filter reactors, also known as harmonic trap reactors, are inductors used in the filtering of harmonics in a power system with capacitors to prevent specific line frequencies from flowing back to the power source. These harmonics are typically caused by non-linear devices in the power system. We can design the harmonic filter reactor to a variety of fundamental frequencies and the accompanying harmonic content of your power system.



  • Single or three phase construction
  • Single phase floating core design up to 125 kV BIL
  • Single and three phase grounded core up to 110 kV BIL
  • Magnetic Specialties core leg construction results in quiet construction
  • Core legs built with multiple small gaps to reduce core loss
  • Conservative design results in long life span
  • Core and coil insulation designed for switching transients of 100% of the system line-neutral voltage across the coil to ground
  • Core and coil designed for operation within specified harmonic spectrum
  • Insulation Class 220C Insulation
  • Aluminum or copper windings



  • Linear to customer specified overcurrent operation
  • Thermal switches or platinum RTDs on grounded core devices
  • Final Test Reports with optional Certificate of Compliance



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