Milliohm Brand HoFL Series Shunt-High Stability Enabled by Precision Alloys

Shunt resistors are used for current sensing, capable of detecting currents ranging from hundreds of amperes up to thousands of amperes. Thanks to their special alloy materials, these shunts exhibit excellent long-term stability and can withstand pulse current surges several times higher than their rated current without damage.

Current Coefficient – Crucial for Current Sensing Applications

For shunt resistors, both their resistance value and surface temperature continuously change as current is applied. Factors causing this resistance change include the temperature coefficient of resistance and dimensional changes due to thermal expansion. When the shunt's heating and heat dissipation reach a dynamic equilibrium, its resistance tends to stabilize. However, an excessively high current coefficient can cause the shunt resistance to deviate beyond its nominal accuracy. The shunt resistor's special material composition, preparation , and heat treatment processes ensure a low current coefficient and excellent compensation characteristics.

Low Thermoelectric EMF and Low Inductance

Since the voltage sensing points always maintain a certain distance from the resistor's heating center, a temperature difference exists between them. Therefore, a low thermoelectric EMF (Electromotive Force) is particularly crucial. These shunt resistors exhibit a copper thermoelectric EMF below 0.5 µV/°C, resulting in a negligible impact on millivolt-level voltage outputs. The shunt's flat structure leads to an inductance of less than 3 nH, ensuring excellent performance even at high frequencies.

Product Features

• High precision
• Strong reliability
• High overload capability
• High stability
• Wide operating temperature range
• Non-inductive design
• RoHS compliant
• AEC-Q200 certified

Product Applications

• Battery Management Systems (BMS)
• Current sensing in power electronic equipment
• Frequency converters (Inverters)
• Motor control
• Electronic load equipment
• Uninterruptible Power Supplies (UPS)