75mV Ammeter Precision Current Shunt

Description

Precision Current Shunt Resistor – 100A 75mV

Engineered for accurate current measurement in high-power applications such as VFDs, battery management, and industrial controls, this precision shunt resistor offers exceptional thermal stability and low TCR.

The 75mV low resistance precision current ammeter shunt resistor is a high-accuracy, low-value resistor used primarily for DC current measurement in industrial systems. It works by generating a voltage drop proportional to the current passing through it, enabling precise readings by a DC ammeter.

How the 75mV Precision Shunt Resistor Works

The shunt operates based on the volt-ampere characteristics of resistance. When DC current flows through the shunt, a voltage drop is produced—typically 75mV—which is read by the ammeter. In essence, the shunt “diverts” a small, measurable portion of the current to allow accurate indication by the meter.

The smaller the ratio between the sampling current (mA) and the primary circuit current (1A to tens of amps), the better the linearity and accuracy of the measurement.

For example:

• A 100A ammeter shunt with a resistance of 0.75mΩ:
  100A × 0.75mΩ = 75mV

• A 50A ammeter shunt with a resistance of 1.5mΩ:
  50A × 1.5mΩ = 75mV

Main Technical Parameters

• Accuracy level:
  2–4000A: 0.5 level;
  5000–10000A: 1 level.

• Environmental conditions:
  Temperature range: -40°C to +60°C
  Relative humidity: ≤95% at 35°C

• Overload capability:
  Withstands 120% of rated current for 2 hours

• Voltage drop options:
  50mV, 60mV, 70mV, 75mV, 100mV

• Heat generation:

  • Rated current ≤50A: temperature rise ≤80°C

  • Rated current >50A: temperature rise ≤120°C

Applications of 75mV Shunt Resistors in DC Measurement

These shunt resistors are widely used in:

• Power supply systems

• Battery monitoring

• Solar energy systems

• Industrial automation

• Electric vehicles

Shunt wiring diagram