Measuring high current in circuits such as DC power supplies requires shunt resistors. Unfortunately, those resistors affect the circuit's performance because of the voltage drop needed to make the measurement in the first place. Plus, shunt resistors generate heat that needs to be managed.


Microhm Electronics' NSR series of metal-foil resistors contain an embedded Pt100 RTD sensor that you can connect to a temperature-measurement circuit or instrument to monitor the resistor's temperature. The drawing below shows the voltage (V1/V2), current (C1/C2), and temperature (Pt100) connections. Connections C1 and C2 are for the resistor itself and they pass the power source's high current. Use the V1/V2 terminals to measure the voltage across the shunt to calculate current.
NSR series shunt resistors are available with values from 0.001 Ω to 1 Ω with a power rating of 500 watt on heatsink. Available tolerances ±0.05% ±0.1%, ±0.5%, and ±1.0%. The TCR can be as low as 1ppm/K or 5 ppm/K. NSR series works as output reference of precision power supply and reference of charge-discharge test for high capacity batteries.