Definition: The diode whose internal capacitance varies with the variation of the reverse voltage such type of diode is known as the Varactor diode. It is used for storing the charge. The varactor diode always works in reverse bias, and it is a voltage-dependent semiconductor device The voltage-dependent device means the output of the diode depends …
Definition: The instrument uses for determining the sequence of the three-phase system is known as the phase sequence indicator. The change in the sequence of the power supply changes the direction of rotation of the machine. Because of which the entire supply system will be affected. For proper connection, it is essential to know the …
Definition: The capacitive voltage transformer step-down the high voltage input signals and provide the low voltage signals which can easily measure through the measuring instrument. The Capacitive voltage transformer (CVT) is also called capacitive potential transformer The capacitive potential divider, inductive element and the auxiliary transformer are the three main parts of the capacitive potential …
Definition: The Weston frequency meter is a moving iron instrument used for measuring the unknown frequency of a signal. The frequency meter consists one inductive and one resistive coil. When the frequency of the signal varies from standard frequency, the current distribution across the coils becomes changes. Working Principle of Weston Frequency Meter The Weston …
Definition: The instrument that measures the low value of power factor accurately is known as the Low Power Factor Wattmeter (LPFW). The low power factor meter is used for measuring the power of the highly inductive circuit. It is also used in the resistive circuit which has a power factor range from 0.5 to 1. …
Definition: The galvanometer in which the oscillation frequency of the moving element and the measurand current becomes equal is known as the vibration galvanometer. It uses for detecting the alternating current or alternating electromotive force. Working Principle of Vibration Galvanometer When an alternating current is passing through the moving element of the galvanometer, deflecting torque produces …
The Wien’s bridge use in AC circuits for determining the value of unknown frequency. The bridge measures the frequencies from 100Hz to 100kHz. The accuracy of the bridges lies between 0.1 to 0.5 percent. The bridge is used for various other applications like capacitance measurement, harmonic distortion analyser and in the HF frequency oscillator. The …
Definition: The instrument which represents the measurand value in the form of the digital number is known as the digital instruments. It works on the principle of quantization. The quantization is the process of converting the continuous input signal into a countable output signal. The construction of the digital instrument is very complex, and their …
Definition: The voltmeter which uses the vacuum tube for amplifying the measurand AC and DC voltage is known as the vacuum tube voltmeter (VTM). The vacuum tube increases the sensitivity of the voltmeter because of which it can detect the signal of very weak strength. The electronic voltmeter is used for measuring the voltage of …
Definition: The voltmeter which uses the amplifier for increases their sensitivity is known as the electronic voltmeter. It is used for measuring the voltages of both the AC and DC devices. The electronic voltmeter gives the accurate reading because of high input resistance. The moving coil voltmeter is not able to detect the low voltages. …
