HRA 520W to 2500W Series High Power Metal Clad Resistor Assemblies

What are the HRA 520W to 2500W Series High Power Metal Clad Resistor Assemblies?

The HRA is a high-power metal clad resistor assembly designed for the most demanding industrial power dissipation applications — inverter braking, motor drive load banks, energy storage discharge, and high-power industrial equipment — where single-body resistors cannot deliver the required wattage within the available footprint. Each HRA assembly houses multiple wire wound metal clad resistor elements within a single rugged steel outer enclosure, with the base constructed from zinc-plated steel and the cover powder-coated and oven-baked for exceptional mechanical durability and long-term corrosion resistance.

Spanning a power rating range of 520W to 2500W, the HRA series bridges the gap between the standard single-body metal clad resistor range and full custom load bank assemblies, providing a pre-engineered, catalogue-standard high-power solution for engineers who need significantly more wattage than a single chassis-mount unit can offer while still requiring a compact, self-contained package. The multi-element construction allows the HRA to achieve both high power dissipation and a broad resistance range of 0.1Ω to 1.6kΩ within a single assembly footprint, delivered in free-air rated configurations that do not require a dedicated external heatsink for operation at rated power.

Both inductive and non-inductive winding configurations are available across the range. The non-inductive option is critical for snubber and high-frequency switching applications where residual winding inductance in the resistive elements would compromise transient suppression performance. Tolerance options of ±0.5%, ±1%, ±2%, ±5%, and ±10% provide flexibility from precision discharge timing through to general industrial load control.

Dielectric withstand voltage options of AC 1500V, 2500V, and 3500V (maximum 2mA leakage current) accommodate medium-voltage industrial bus architectures, while insulation resistance is rated at 20MΩ minimum. The operating temperature range of –55°C to +200°C and a TCR of ±260 ppm/°C maximum ensure stable, predictable resistance across the full spectrum of industrial ambient conditions. Short-time overload capability is rated at 10× the nominal wattage for 5 seconds — confirming the robustness demanded by repetitive high-energy transient duty cycles in motor control and energy recovery platforms.

Characterisation testing covers moisture resistance (40°C / 95% RH for 500 hours), thermal shock (rated power for 30 minutes followed by –25°C for 15 minutes), and extended load and moisture load life testing — ensuring long-term electrical stability and mechanical integrity under continuous industrial duty conditions.

Model: HRA
Resistor type: Metal clad resistor
Description: Assembly
Power Rating: 520W-2500W
Resistance (Ω): 0.1~1.6k
Tolerance (%): ±0.5, ±1, ±2, ±5, ±10
TCR (ppm/C): 260 Max.

Model: RA
Resistor type: Metal clad resistor
Description: Assembly
Power Rating: 80W~750W
Resistance (Ω): 0.1~2.2k
Tolerance (%): ±0.5, ±1, ±2, ±5, ±10
TCR (ppm/C): 260 Max.

Model: LCA
Resistor type: Metal clad resistor
Description: Assembly
Power Rating: 1kW-4.2kW
Resistance (Ω): 0.6~864
Tolerance (%): ±5, ±10
TCR (ppm/C): 260 Max.

Model: MCS
Resistor type: High Power Braking
Description: Industrial
Power Rating:2kW-3.4kW
Resistance (Ω): 0.1~9k
Tolerance (%): ±1, ±5, ±10
TCR (ppm/C):

Model: MBVA
Resistor type: Metal clad resistor
Description: Assembly
Power Rating: 3.3kW-8.5kW
Resistance (Ω): 0.5~100
Tolerance (%): ±5, ±10
TCR (ppm/C): 260 Max.