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Maxwell Inductance Bridge Circuit

For measurement of inductance, the Maxwell Bridge shown in figure 1 can be employed. It is seen that the circuit of the Maxwell Bridge is simply a repeat of the series resistance-capacitance bridge, with the capacitors replaced by the inductors. Fig.1: Maxwell Bridge  A disadvantage of this bridge is that the …

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Series Resistance Capacitance Bridge Circuit

One disadvantage of simple Capacitance Bridge is that perfect balance of the bridge is obtained only when Cs and Cx are both pure capacitances (i.e. they have virtually no resistive components). In general, this occurs only with capacitors that have air or mica dielectrics. Capacitors with other types of dielectric …

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Capacitance Bridge Working Principle

AC bridges are used for measurement of inductances and capacitances. All AC bridge circuits are based on Wheatstone bridge. Figure 1(a) shows the circuit of a simple capacitance bridge. Cs is a precise standard capacitor, Cx is an unknown capacitance, and Q and P are standard resistors, one or both …

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Digital Multimeter Working Principle

    Fig.1: Digital Multimeter There are two main types of multimeters.  One of the first and oldest multimeters is the analog meter, (Figure 2) and the other, now more widely used meter is the digital multimeter (Figure 1). Fig.2: Analog Multimeter Analog Multimeter Analog meters are a multifunctional multimeter that …

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Wire Gauge Sizes | Circular mils

In order to compare the resistance and conductor sizes with each other, we need to establish a convenient unit. This unit is the mil-foot (mil-ft). A conductor will possess this unit size if having one mil (0.001 inches) diameter and a length of one foot. The standardized unit for wire …

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Impedance Measurement Theory

AC Bridge Circuit

The opposition that a circuit offers to the flow of AC is called impedance. By measuring the voltage and current in an AC circuit and utilizing the following equation $Z={}^{V}/{}_{I}$ We can obtain the magnitude of circuit impedance. However, it is often desirable to separate impedance into resistive and reactive …

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Ohmmeter Basic Concepts and Working Principle

Ohmmeter Definition An ohmmeter is an instrument used to measure the resistance. It is an instrument containing a voltage source and a meter directly calibrated in ohms. Series Ohmmeter One type of ohmmeter is the series ohmmeter, so called because the meter movement is in series with the source of …

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Digital Voltmeter Circuit and Working Principle

In digital voltmeters, input quantity is a voltage or is converted into a voltage. Normally, digital voltmeters are abbreviated as DVM. The process by which a DVM converts the analog input into digital output is known as analog to digital conversion. The basic conversion processes are the comparison and voltage …

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Oscilloscope Basics | What is an Oscilloscope

“Oscilloscope is most widely used to display amplitude and period of the signal as well as the shape of the wave.” Anything can be measured on the two-dimensional graph drawn by an oscilloscope. Normally, voltage is displayed on the vertical, or Y-axis and time on the horizontal, or X axis …

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