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Analog Multimeter Working Principle

Taking a reading with an analog multimeter

An analog multimeter is a meter that can measure two or more electrical properties and display the measured properties along calibrated scales using a pointer. Analog multimeter uses an electromechanical component called a D’Arsonval movement to move the pointer along the scales to display measured values when the test leads …

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Electronic Voltmeter Working and Block Diagram

Electronic Voltmeter

An analog electronic voltmeter uses an electronic amplifier to improve the performance of an electromechanical voltmeter. For example, an electronic voltmeter has a much higher input resistance than an electromechanical instrument, so voltmeter loading effect is considerably reduced. Also, voltage levels that are normally too small for measuring on an …

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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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