Understanding Current Shunt Resistors

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There are many types of current shunt resistors available in the market. Resistance is one of the most important factors when you build a solar panel or use batteries to power your appliances. If the current passing through an individual conductor of a cell can be changed by the addition of a varying current then the overall performance of the cell will be affected. The amount of current flowing through a cell is known as its "effective" current and its path through the cell is called its "permanent" current. Both are important to your solar power system design.
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A current shunt is a device that helps change the current's resistance to the alternating current. A current shunt has a certain resistance which decreases as the current passes over it. For instance, a 1-ourious resistive cell will always have a minimum resistance of 1 ohms, with a maximum resistance of 0.5 ohms at maximum amp load. A current shunt will help change the resistance to a higher value. For instance, if a five amps current shunt was used, the voltage drop across the cell would be greater than five volts.

How are current shunts used? Current shunts are used in many different applications in the battery and solar power industry. There are both electrical and mechanical devices that help reduce the resistance through the resistivity material. The two types of Metal Clad Braking Resistors are thermal and permanent. The difference between the two is that a thermal device dissipates its heat away from the interior surface of the circuit, while a permanent one is solid and does not dissipate heat. Thermal conductors allow more current to pass through them, which creates a smaller voltage drop across the cell.

How do current shunt resistors help to lower the current? When you take a look at the circuit, or when you listen to the generator running, you will notice that the current is a little higher than the rated current. This is because of the shunt created. This current shunt forces the current to go down to the primary circuit. The secondary current then flows through insulated conductors to the battery.

Are shunts made of metal all the same? No. Different metals have different conductivity and are suited for different applications. The best current shunts use the best metals and are tested for their ability to reduce the voltage drop across the cell.

Where can I get current shunts? You can find them in most auto parts stores. They are available as part of an electrical system package. Or, shop online. Be sure to choose the right size and current shunt rating that will fit your application. View here for more information related to this topic: https://en.wikipedia.org/wiki/Resistor.