The core parameters of shunt resistors mainly include the following categories:
Basic electrical characteristic parameters
Resistance Value:
Definition: The resistance of a shunt resistor, usually measured in milliohms (m Ω) or micro ohms (μ Ω).
Importance: The resistance value determines the voltage division and shunt effect of the shunt resistor in the circuit, and is the basis for current measurement.
Accuracy (tolerance):
Definition: The allowable deviation range of the resistance value of a shunt, usually expressed as a percentage.
Importance: High precision can ensure the accuracy of current measurement, which is particularly important for applications that require precise control of current.
Temperature Coefficient of Resistance (TCR):
Definition: Refers to the ratio of the resistance of a shunt that changes with temperature, usually measured in ppm/℃ (parts per million/degree Celsius).
Importance: The low temperature coefficient ensures that the resistance variation of the shunt resistor at different temperatures is within an acceptable range, thereby ensuring the accuracy of current measurement.
Power processing capability parameters
Rated Power:
Definition: The maximum power that a shunt resistor can withstand under long-term operation, usually measured in watts (W).
Importance: The rated power determines the maximum current that the shunt resistor can carry and is a key parameter to consider when selecting a shunt resistor.
Pulse Power:
Definition: The maximum power that a shunt resistor can withstand in a short period of time, usually higher than the rated power.
Importance: For application scenarios that require withstanding pulse currents, pulse power is an important consideration factor.
Physical and structural parameters
Package Size:
Definition: The physical dimensions of a shunt resistor, typically expressed in length, width, and height.
Importance: The packaging size affects the installation and layout of shunt resistors on the circuit board.
Heat Dissipation Structure:
Definition: Diverter resistors are used in the design of heat dissipation, such as heat sinks, heat dissipation holes, etc.
Importance: A good heat dissipation structure can ensure that the shunt resistor maintains a low temperature under long-term high current operation, thereby extending its service life and improving reliability.
Material:
Definition: The manufacturing material of shunt resistors, such as manganese copper, nickel chromium and other alloy materials.
Importance: The material determines the electrical and mechanical properties of the shunt resistor.
Application related parameters
Response Time:
Definition: The response speed of a shunt resistor to changes in current, usually measured in microseconds (μ s) or nanoseconds (ns).
Importance: For application scenarios that require rapid response to current changes, such as pulse current measurement, response time is an important consideration factor.
Operating Environment Conditions:
Definition: The environmental conditions under which a shunt resistor can operate normally, such as temperature range, humidity, vibration, etc.
Importance: The working environment conditions affect the reliability and lifespan of the shunt resistor, and it needs to be selected according to the actual application scenario.