Light Dependent Resistors (LDRs) - Definition, Construction, Workings and Applications: Light dependent resistors (LDRs) are made from cadmium sulphide containing no or very few free electrons when not illuminated. Its…
What is Backward Diode? A tunnel diode designed to provide a small peak current (IP of the order of IV) may be employed to advantage in the reverse direction, for…
Microprocessor Based Protection Relay: Reliable and accurate protection schemes are required for any system. Microprocessors can fulfill these requirements without fail. In addition to the system protection, microprocessors can perform…
Measurement of Electrical Quantities: Measurement of electrical quantities which includes Measurement of Voltage Measurement of Current Frequency Measurement Phase-Angle Measurement Power-Factor Measurement Impedance Measurement VA Measurement Power Measurement VAR Measurement…
Phototransistor Construction and Working Principle: The sensitivity of a photo diode can be increased by as much as 100 times by adding a junction, resulting in an NPN device. A…
Carrier Pilot Protection and Microwave Pilot Protection: The problem of providing economically an auxiliary channel by means of pilots for long lines directed attention to carrier techniques. In this case…
Optocoupler Circuit Operation: An Optocoupler Circuit Operation (optoelectronic coupler) is essentially a photo-transistor and an LED combined in one package. Figure 20-35(a) and (b) shows the typical circuit and terminal…
TRIAC Control Circuit Diagram: A TRIAC Control Circuit Diagram that allows approximately 180° of phase control is shown in Fig. 19-27(a). The waveforms in Fig. 19-27(b) illustrate the circuit operation.…