Precision DC Current Shunts

Riedon has expanded its line of precision current shunts to include current ratings up to 10,000 amps. The RS series of off-the-shelf, base-mounted and bus-bar shunts now offers current ratings from 5 A to 10,000 amps and a number of mounting configurations to meet various installation requirements. The RS series and now the RCS, RSH, RSI, RSJ, RSL, and RSN series still manages to combine low cost with the industry's shortest lead-times, while Riedon's custom design capability caters to unique requirements. These devices are targeted at applications in the renewable energy market, high capacity battery monitoring, and heavy industry.

The principle of current measurement using a shunt resistor depends on measuring the small voltage dropped across a precision resistor placed in series with the load. Riedon offers standard parts that provide 50 mV and 100 mV outputs, but can also provide custom output voltages. The very-low-resistance values required for shunt resistors, 10 mΩ at 5 A and just 0.005 mΩ at 10,000 A, are provided by Manganin® resistive elements. These are precision-etched to a standard tolerance of ±0.25%, while the RSN series features a tolerance of ±0.1%.

Riedon's RS range is divided into different families depending on current rating and mounting style. All feature a 4-terminal design, which separates the heavy-duty load carrying connections from the voltage-sensing terminals. Terminals blocks are either brass or copper depending on series and current rating.. Operation is specified over a temperature range of -40°C to +80°C with a temperature coefficient of resistance (TCR) of ±15 ppm/°C or better and a dielectric strength for base mounted models of of 750 V_DC (terminal block to base).