What is Shunt Resistor
A shunt is a resistor connected in parallel with an ammeter as a shunt in order to expand the current measurement range. Recently, resistors for current detection that detect circuit current are collectively called shunt resistors.Shunt Resistor (Classification)
Historically, shunt referred to a resistor connected in parallel to an ammeter for sorting purposes. Shunt meaning "to deflect," "avoid," or "sort."In order to expand the measuring range of the ammeter, the total current flowing is measured by connecting a resistor in parallel to the ammeter.
For example, the total current (Im) flowing through the upper circuit is expressed by the following formula. Im=Ir+Ir (r/R)=Ir (1+r/R)
Therefore, the ratio of the total current flowing through the circuit to the current flowing through the ammeter is Im/Ir= (1+r/R)
In other words, (1+r/R) times the display of the ammeter (Ir: current flowing through the ammeter) becomes the total current flowing through the circuit.
Shunt Resistor (Series):
In a circuit in which resistors are connected in series, the potential difference (voltage drop) across the resistor is detected, and the current flowing through the circuit is measured using Ohm's law.
For example, as current (I) flows, a potential difference (V) is created across the resistor.
The potential difference that occurs can be calculated using Ohm's law. V = I × R (Ohm's Law)
By detecting the voltage (V) in the detection circuit, the current (I) flowing through the circuit can be measured. Since the current (I) and voltage (V) are proportional, in reality, the change in the current value (I) is substituted for the detected voltage (V) change and used for feedback control and threshold monitoring
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