LPS / ULPS Series Low Cost Precision Shunt Resistors

What are the LPS / ULPS Series Low Cost Precision Shunt Resistors?

The LPS and ULPS are four-terminal precision shunt resistors of metal clad construction, designed for accurate high-current measurement in power electronics and industrial applications. The Kelvin connection architecture physically separates the current-carrying terminals from the voltage-sensing connections, eliminating the contact resistance errors that afflict conventional two-terminal shunt designs. This separation allows the voltage drop across the purely resistive element to be sampled independently of the high-current path, delivering the measurement accuracy demanded by battery test systems, precision power sources, and energy conversion equipment.

The resistance range spans 0.1666mΩ to 0.5mΩ, covering the low-impedance requirements of high-current bus applications. Rated current extends from 100A to 300A, with tolerance options of ±0.5% and ±1% providing a choice between economy and precision depending on the measurement accuracy required. The temperature coefficient of resistance is available at 15 or 30 ppm/°C, with the tighter 15 ppm/°C grade ensuring measurement stability across the operating temperature range typical of power conversion environments. The metal clad body provides a high load capacity in a compact form factor, enabling installation directly onto current bus bars without the bulk associated with traditional shunt resistor assemblies.

The heavy copper terminals are dimensioned for low-resistance bolted connections to bus bars, minimising the self-heating and contact instability that would otherwise degrade measurement accuracy at high sustained currents. Low inductance is a further characteristic of the construction, ensuring that the voltage signal across the sense terminals accurately represents the resistive voltage drop even during fast transients in switching converter applications. The ULPS variant adds UL certification to the same electrical design, meeting the agency approval requirements of markets where certification is a precondition for system approval. Both versions are mechanically interchangeable, allowing a common PCB or mechanical design to serve either standard or UL-certified configurations.

Model: LPS
Resistor type: Current sensing
Description: Low cost precision
Rated Current: 200A~300A
Resistance (Ω): 0.1666m~0.25m
Tolerance (%): ±0.5, ±1
TCR (ppm/C): 15, 30

Model: IRHF
Resistor type: Current sensing
Description: High power precision
Rated Current: 30A~500A
Resistance (Ω): 0.2m~3.333m
Tolerance (%): ±0.1, ±0.5, ±1
TCR (ppm/C): 15, 30

Model: AH
Resistor type: Current sensing
Description: Four terminal precision
Power Rating: 3W, 10W
Resistance (Ω): 1m~100
Tolerance (%): ±0.1, ±5, ±1
TCR (ppm/C): 10

Model: HPS
Resistor type: Current sensing
Description: High power precision
Power Rating: 250W
Rated Current: 387A max.
Resistance (Ω): 1m~100m
Tolerance (%): ±0.05, ±0.1, ±0.5, ±1
TCR (ppm/C): 3, 5, 10

Model: UHPS
Resistor type: Current sensing
Description: Ultra high power precision
Power Rating: 100W
Rated Current: 707A max.
Resistance (Ω): 0.2m~1m
Tolerance (%): ±0.05, ±0.1, ±0.5, ±1
TCR (ppm/C): 3, 5, 10