Specifying a shunt resistor Several parameters are important to specifying a shunt galvanometer. A shunt resistor has a maximum rated current. The resistance value is given by the voltage drop of the maximum rated current. For example, shunt resistors rated for 100A and 50mV have a resistance of 50/100 = 0.5 mohm, and the voltage drop at maximum current is usually rated for 50.75 or 100my. Other important aspects include positive tolerance, positive temperature coefficient, and rated power, which is the amount of energy a resistor can consume at a given ambient temperature without damaging or changing the resistance parameters. The generated power can be calculated using Joule's law. For continuous operation, the derating factor of a shunt resistor is usually 66%. This is defined for run times of more than two minutes. High temperature will negatively affect the accuracy of the shunt.

It starts at 80 degrees Celsius. The situation gets worse as the temperature increases, from 140 degrees, the resistance will be damaged and the resistance value will change permanently. What is a shunt in electronics? We have introduced a shunt generator whose main purpose is to measure current. However, in electronics the term shunt has a broader meaning than this. A shunt is a component of a circuit used to divert current around another part. Applications vary widely. For some applications, electrical devices other than resistors may be used. Several examples are given to illustrate the diversity of diverters. One way to protect a circuit from overvoltage, to protect a circuit from overvoltage, is to use a crowbar circuit. When the voltage is too high, the equipment will short out.

This causes the current of the shunt resistor to flow parallel to the circuit, which immediately causes the voltage in the circuit to drop. A large current passing through the shunt should trigger a circuit breaker or fuse. When a single element in a series circuit fails, it destroys the entire circuit. A shunt can be used to overcome this problem. The higher voltage due to the fault will cause the shunt to short circuit. The current will pass through the defective component. Christmas lighting is a case in point. Bypass noise diverters with capacitors are sometimes used in circuits plagued by high frequency noise. The capacitor redirects the noise to the ground before the unwanted signal reaches the circuit element.