Blogs

24-Jan-2025

Shunt resistors are a crucial part of electronic circuits, and their prime role is to measure current by maintaining a record of the extent of voltage drops. They turn out to be very useful in applications where precise measurement of current is needed for operation like that of an automotive system, renewable power generation setup and industrial machinery. To acquire a sophisticated comprehension of the shunt resistor terminology is crucial for engineers and technicians. The demand for shunt resistors continues to be high in the current market and the future looks favorable for this electronic component. The Shunt resistor market was USD 3.1 billion in 2023 and could reach USD 5.2 billion by 2032. The growth rate that will increase its value is a CAGR of 5.8%. Such rising growth can be attributed to a fast rise in demand for EVs and solar-powered devices. These areas of industries increase the demand for more shunt resistors along with electronic goods. Renewable energy is one of the rising factors increasing the demand for shunt resistors. How Do Shunt Resistors Function? Shunt resistors work through creating a voltage drop across the "known value" resistor when it has current running through it. The voltage drop is then read using a voltmeter, and the value, once obtained, is usually amplified, then used in a calculation for the current going through the circuit. Measuring the current flow of a circuit is done by doing a calibration of the voltage drop across the shunt resistor with known current value, and afterwards the output voltage is adjusted by removing resistive material until the values coincide perfectly. As the current requirements increase, the resistance has to be reduced for detection of smaller current measurements. The output from the shunt resistor is usually in the range of 0 to 100mV. This is usually too minute to record by most processors so the signal is usually amplified and converted to a digital signal. Selecting an analog-to-digital converter with a high resolution will allow you to oversize your shunt while still having great accuracy when measuring low currents.  Why is Shunt Resistor Important? High voltage surges can damage circuit components, and a large circuit, such as in your home, has many expensive electrical appliances that can be costly to repair or replace if damaged. A shunt resistor can be a safety component used to protect the circuit against voltage surge. This is done by a crowbar circuit, which consists of a shunt resistor. At higher voltage, this short circuits the device, which causes the voltage to drop instantaneously. Shunt resistor is the part of this circuit that brings about the short circuit because it senses a high current.  Keeps Circuit Operational Despite Faulty Component A fault in even one component attached in a circuit can break the current loop rendering the entire circuit non functional which shuts off all devices connected to the circuit. The problem is resolved by using a shunt resistor. The break in the current loop is avoided as the shunt will short circuit in case of excessive voltage and the electricity will bypass the faulty component. High frequency noise in many electronic circuits causes performance degradation and interference in the signal. A shunt resistor will prevent the unwanted signal from entering the circuit components by redirecting the signal to the ground. What To Know When Selecting a Shunt Resistor Current Rating Shunt resistors are rated for a maximum current. The manufacturer provides the maximum current rating. How much a voltage drops at the max current rating will indicate the resistance value of the resistor. To illustrate, a shunt resistor rated 100 A and 50mV has a resistance value of 50/100 =0.5mΩ. Power rating This is defined as maximum energy that can be dissipated by a resistor according to Joule's Law. More power rating is to be found in large shunt resistors, which have a wide surface area. The shunt resistor will get damaged if power dissipation exceeds the power rating of the resistor. Temperature Coefficient of Resistance (TCR) This is a crucial indicator of resistor performance. It is defined as the change in resistance with respect to ambient temperature. TCR values are very crucial for determining the suitable shunt resistor. Applications of Shunt Resistors Renewable Energy Systems If we look further at the research results, we will see a rise in demand for shunt resistors in renewable energy. Solar inverters require shunt resistors in order to safely carry current flows. It shows a massive consumption rate in the installation process. Also, in this case, it involves using shunt resistors in battery management systems for the accurate measurement of current. Automotive and Electric Vehicles In the last few years, the demand for EVs has increased dramatically. Europe and North America are the countries where the usage of EVs is most prevalent, which leads to increasing shunt resistor demand. Their battery management systems, among other configurations, have miniaturized components to carry safe current. Electronic Devices The electronic industry already harbors a steady demand for shunt resistors, further by the growing demand. This increase has been due to innovation in smartphones, laptops, and wearable devices. The use of shunt resistors in their power supplies and power meters shows a massive consumption rate. It shows that industrial automation equipment also has a rise in demand for shunt resistors. Battery modules and radiofrequency transceiver modules also contribute to an increase in the demand size of shunt resistors. Conclusion Shunt resistors are among the major components of future innovations. Solar technology and electric vehicles are already rapidly growing in the consumer industry. Since they require a safe current flow against risks of short circuits and fluctuations, shunt resistors are installed inside their battery management systems. Similarly, shunt resistors are also experiencing parallel growth in similar industries. The basic aspect of a shunt is the existence of a resistive element whose value is known, with a voltage drop across it, thus providing an idea of how much current passes through the circuit, whether much power is drawn, or whether there is a short. This calls for having an accurate shunt for one to have a precise view of the status of the electrical circuit.

04-Sep-2024

When it comes to circuit functionality many components play a role and one of them is a shunt resistor. Shunte resistors also function as a safety component to prevent damage to the circuit during voltage surges. But that is not their sole function and shunt resistors have other applications also. In this blog we will take an in-depth look at the shunt resistor and its applications and how to choose one for your project. What is a Shunt Resistor? A shunt resistor is a kind of resistor that measures the current flow in a circuit. The shunt resistor should be connected in series with the circuit. The voltage across the resistor indicates the current flowing through a circuit. Why Are Shunt Resistors Important? Current measurement by using a shunt resistor is necessary in a circuit for various reasons. One vital reason to measure current flow is to confirm if the current is within the safe limit so that it does not damage the circuit components. Many issues can also be fixed within the circuit by current measurement through a shunt resistor. For instance, you can determine whether a current flow is sufficient for a particular component on the circuit. A lack of current means that the component is faulty. A Look at Shunt Resistor Applications Now, let's have a look at the shunt resistor applications Safety Component Against Voltage Surge High voltage surges can damage components of a circuit, and a large circuit, such as in your home, has many expensive electrical appliances that can be costly to repair or replace if damaged. A shunt resistor can be a safety component used to protect the circuit against voltage surge. This is done by a crowbar circuit, which consists of a shunt resistor. As the voltage gets high, the device short circuits, which immediately leads to a voltage drop. The shunt resistor is the key component that triggers the short circuit as it registers the high current. Helps Bypass a Faulty Device in a Circuit A fault in even one component attached in a circuit can break the current loop rendering the entire circuit non functional which shuts off all devices connected to the circuit. A shunt resistor is used to overcome this issue. The break in the current loop is avoided as the shunt will short circuit in he event of an excessive voltage and the electricity will bypass the faulty component. Bypass Electrical Noise In many electronic circuits high frequency noise can affect performance and lead to signal interference. A shunt resistor prevents the undesired signal from reaching the circuit components by redirecting the signal to the ground. Choosing the Correct Shunt Resistor: Factors to Consider If you plant to include a shunt resistor in circuit design you must know about various shunt resistor specifications to select the right resistor. Following are the specifications to keep in mind. Current Rating: Shunt resistors have a maximum current rating that is specified by the manufacturer. How much a voltage drops at the max current rating indicates the resistance value of the resistor. To illustrate, a shunt resistor that has a rating of 100 A and 50mV has a resistance value of 50/100 =0.5mΩ. After finding out the maximum current rating, you will be able to Temperature Coefficient of Resistance (TCR): This is an important indicator of resistor performance. It is defines as change in resistance regarding ambient temperature. TCR values are essential for determining the suitable shunt resistor. Power Rating: This is defined as maximum energy that a resistor can dissipate according to Joule’s Law. Large shunt resistors with a wide surface area have a higher power rating. If power dissipation exceeds the power rating of resistor than the shunt resistor will get damaged. Conclusion When choosing a shunt resistor, there are crucial parameters that must be taken into consideration including the resistance value, power rating, tolerance and temperature coefficient. It is, therefore, important that you comprehend the need of your circuit, the current measurement range you need and the accuracy that you require to measure the current to ensure that you find the best resistor that is reliable and meets the requirements of the circuit. Further, considering the size, material and the way it is mounted will make it possible to complement with your circuit design. The implication, therefore, is that when you make an informed decision, you will be in a position to improve on the quality, speed and durability of the electrical projects that you undertake, and therefore, the outcomes that you are going to achieve.