Line Reactor & Chokes

Line Reactor
& Chokes

These devices are typically connected in series with power lines, either at the input side (line side) of equipment or at the output side (load side), depending on the intended function:

  • On the input side, line reactors protect Variable Frequency Drives (VFDs), UPS systems, and other power conversion equipment against sudden voltage fluctuations, switching surges, and line disturbances. By introducing a small but controlled impedance, they reduce the rate of rise of current, mitigate harmonic currents, and lower the risk of drive tripping due to line disturbances.

  • On the output side, reactors help in protecting motors and connected loads from voltage spikes caused by long cable runs, reflected wave phenomena, and fast switching of power semiconductor devices inside VFDs. This ensures smoother motor operation, extended motor insulation life, and reduced mechanical stress.

Line Reactor & Choke – Technical Specification

ParameterSpecification
GeneralPassive inductive component for limiting current, suppressing harmonics, and protecting equipment (VFDs, UPS, motors). Installed on input (line side) or output (load side).
Standards & ComplianceIEC 60076, IEC 61558, IEEE C57.16, UL 508C, IEC 61000 (harmonic & EMC compliance)
System Voltage230 V / 400 V / 415 V / 480 V / 690 V (other ratings on request)
Frequency50 Hz / 60 Hz
Rated Current5 A – 2000 A (custom up to 5000 A)
Impedance1% – 2% (light harmonic filtering)
3% – 5% (standard harmonic mitigation)
Short Circuit Withstand10 × rated current for 1 s (IEC 60076)
InductanceApplication-dependent (e.g., ~1.2 mH for 100 A, 415 V, 3% impedance)
Insulation ClassF (155°C) or H (180°C)
Dielectric Strength3.0 kV AC for 1 minute
Core MaterialLow-loss CRGO silicon steel laminations (ferrite for high frequency)
WindingsCopper (aluminum optional), varnish impregnated
CoolingNatural air (AN) standard; Forced air (optional)
MountingPanel or floor-mounted, vibration-resistant base
Protection DegreeIP00 (open type)
Optional: IP23 / IP31 / IP54
Ambient Temperature–25 °C to +50 °C (derating required above 50 °C)
Humidity≤ 95% (non-condensing)
Altitude≤ 1000 m (derating required above 1000 m)
Installation LocationIndoor (outdoor version available with weatherproof enclosure)
Applications– VFD input/output protection
– Harmonic reduction
– Inrush & short-circuit current limiting
– Motor surge protection
– DC link current smoothing
– UPS & renewable system filtering
Typical ExampleVoltage: 415 V AC, 50 Hz
Current: 100 A
Impedance: 3%
Inductance: 1.2 mH
Insulation: Class F
Protection: IP23
Cooling: Natural Air (AN)
TestingRoutine Tests: Insulation resistance, winding resistance, HV test
Type Tests: Temperature rise, short-time withstand test
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