Ultra high-precision current-sense resistor range kicks off at 0.001ohm

VPG Foil Resistors has announced that its Powertron brand S-Line of precision Bulk Metal Foil current sense resistor offering has expanded with the new SHLR series. For industrial and energy applications, the SHLR 4-2321, SHLR 4-3825, and SHLR 4-3825H are the industry's first such devices to combine low resistance down to 0.001ohm, TCR to ±2ppm/K, and high power ratings up to 50W, says the company. Offering load stability to 0.1% for up to 2,000 hours, the resistors provide highly-accurate and reliable current measurement in industrial instrumentation and battery management systems, as well as smart energy grids and solar and wind inverters. For these applications, the devices feature a wide range of power ratings - from 3W in free air to 50W when mounted on a heatsink - and resistance values from 0.001ohm to 0.005ohm with tight tolerances to ±0.1%. The SHLR series achieves its very low TCR in the standard working range of +20C to +60C due to Bulk Metal Foil technology based on CuMnSn metal foil. Its nearly flat TCR curve will help engineers to design more precise equipment or to upgrade existing systems. SHLR series resistors feature maximum currents to 150A, very low inductance, thermal EMF of <1µV/K, thermal resistance down to 1.6K/W, and an operating temperature range of -40C to +130C. Offered in anodized aluminium packages, the devices are RoHS-compliant and lead (Pb)-free, says the company.