A current shunt resistor is a low-resistance path for an electrical circuit. It allows the current to pass around another point in the circuit instead of through it. The term shunt comes from the verb 'to shunt,' meaning to turn away or take a different path. There are many applications for a shunt resistor. Read on to learn more about the basics.
The current shunt resistor's resistance varies very little with temperature. The resistance changes by as little as 0.002% or 20 ppm per degree Celsius. So, for a 30 degree Celsius change, the shunt output will be 0.310 mV off. And, for a 50-degree temperature change, the error is as small as 0.155 mV. As you can see, this is a very important piece of information.
Thermal EMF and TCR are two major characteristics of a current shunt resistor. These parameters affect the accuracy of the current measurement. For this reason, it is important to consider both TCR and thermal EMF when choosing a current sense resistor. A good temperature coefficient will help reduce the errors associated with measuring the current flow through a shunt. A thermal EMF of less than 1% is considered acceptable for most applications.
A shunt resistor's value and power rating will determine its capacity to dissipate power at a given temperature. To calculate the power dissipation, you need to multiply the shunt resistor's resistance value by its maximum current. If you're working with a circuit with a high power-rating, a 50 mili-ohm shunt resistor will allow up to 2A of current. If you're using a shunt for continuous operation, you can assume it will have a derating factor of 66 percent.
Using a high power resistors in a continuous-duty application is generally a safer and more reliable solution than a standard shunt resistor. Since it has a low ohmic value, it's a highly efficient solution to various problems related to electrical power. A current shunt resistor should have a rated power of more than 200W. You must consider the voltage and temperature coefficient of shunt resistors to ensure that they're working safely for your particular application.
A shunt resistor's maximum value, also known as its ohmic value, can be used to measure the amount of current in a circuit. Shunt resistors are used for detecting currents in large motors. It is also possible to use a shunt resistor to detect a low-level voltage. The value of a shunt resistor is directly proportional to its input current.
A shunt resistor's TCR value is a parameter indicating how much the resistance changes with temperature. For a shunt resistor, the TCR should be low or zero, or else the device won't function properly. During a current shunt resistor's lifetime, it must be replaced at least every three years, depending on its age. When a shunt resistor fails to meet these requirements, it can be dangerous and can cause an electrical fire. Check out this related post https://www.encyclopedia.com/science-and-technology/computers-and-electrical-engineering/electrical-engineering/resistor to get more enlightened on the topic.