Definition: When the beam of the light enlightens the surface of the metals like sodium, potassium, caesium and rubidium then their electrons start emitting. The phenomenon of emission of electrons is known as the photoelectric emission. In other words, the photoelectric emission is the process through which the free electrons are liberated from the surface …
Definition: The potential barrier in the PN-junction diode is the barrier in which the charge requires additional force for crossing the region. In other words, the barrier in which the charge carrier stopped by the obstructive force is known as the potential barrier. How It gets established? When the P and N-type semiconductor material are placed …
Definition: The phototransistor is a three-layer semiconductor device which has a light-sensitive base region. The base senses the light and converts it into the current which flows between the collector and the emitter region. The construction of phototransistor is similar to the ordinary transistor, except the base terminal. In phototransistor, the base terminal is not …
Definition: The diode in which the intrinsic layer of high resistivity is sandwiched between the P and N-region of semiconductor material such type of diode is known as the PIN diode. The high resistive layer of the intrinsic region provides the large electric field between the P and N-region. The electric field induces because of …
Definition: The tunnel diode is a highly conductive, heavily doped PN-junction diode in which the current induces because of the tunnelling. The tunnelling is the phenomenon of conduction in the semiconductor material in which the charge carrier punches the barrier instead of climbing through it. The tunnel diode is a heavily doped PN-junction diode. The …
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. …
