IRF series

Supporting Manufacturer Information

IRF Downloads


The IRF series from RARA consists of metal-clad, wirewound, high-power resistors, specifically designed for industrial use and other areas where space efficiency is essential. These low inductance resistors are perfectly suited for applications such as motor drives, braking, snubber applications, and powering industrial equipment. They feature a compact, flat design that not only conserves space but also promotes excellent heat dissipation.

The series is encased in an extruded aluminium housing, which provides robust protection and is ideal for challenging environments, and is available with flying leads. This design choice contributes to the IRF resistors’ suitability for a range of industrial applications. They offer a significant power rating of up to 500W when mounted on a heat sink, with resistance values ranging from 1Ω to 5.78kΩ.

Customers can choose between cement or silicone filling materials based on their specific needs. The IRF series is marked by its precise and reliable performance, thanks to tolerances as low as ±0.5%. These resistors can operate effectively over a wide temperature range, with cement variants handling temperatures from -55℃ to +200℃, and silicone variants from -55℃ to +150℃. Additionally, they have a maximum Temperature Coefficient of Resistance (TCR) of ±260ppm/℃, with tolerances ranging from ±0.5% up to ±10.0%, making them a versatile and reliable choice for demanding industrial applications.

RARA IRN/ULN/IRF/ULF Flat Type Metal Clad Wire Wound Resistors
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 1.1kΩ
  • Power rating of 100W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 1.75kΩ
  • Power rating of 150W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 2.2kΩ
  • Power rating of 200W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 2.79kΩ
  • Power rating of 250W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 3.5kΩ
  • Power rating of 300W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 4.45kΩ
  • Power rating of 400W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant
  • RARA
  • Flat type metal clad wire wound resistor
  • Resistance options from 1Ω up to 5.78kΩ
  • Power rating of 500W (on a heat sink)
  • Tolerance options between ±0.5% and ±10.0%
  • TCR of +260 ppm/°C maximum
  • For UL Approval see the ULF Series
  • Compliant