Saturable Reactors

MSI Saturable Reactor

Saturable Reactors

Saturable reactors, also known as magnetic amplifiers, use a DC control winding to control the flow of AC power in a circuit. By using a saturable reactor in the primary circuit of a power transformer, the output power to the load can be controlled. This is helpful for driving a variety of loads including motors, furnaces, and even lighting equipment. Because there are no fans or solid-state devices, saturable reactors can operate in environments that would be harmful to silicon-controlled rectifier power supplies due to high temperatures or unclean conditions. Magnetic Specialties can design saturable reactors to fit existing control schemes.


  • Up to 1000 KVAR
  • Up to 25 kV class, 125 kV BIL
  • Linear input/output characteristics
  • High resolution output control
  • Self-cooled, forced-air cooled, or water cooled
  • Aluminum or copper windings



  • UL Recognized insulation system (Primary must be 600V or less). MSI UL Insulation systems are available in 130°, 180° and 220°C ratings
  • CE marking with declaration of conformity. ROHS and Low Voltage Directive where applicable
  • Private labeling with customer supplied nameplate artwork. Units that are private labeled cannot carry our UL label
  • NEMA 1 (indoor) or NEMA 3R (outdoor) enclosure with ANSI 61 gray powder coat finish
  • Final Test Reports with optional Certificate of Compliance



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