Functions of Instrument Transformers (CTs and PTs)
AC type protective relays are actuated by the current and voltage supplied by the current and potential (voltage) transformers which are generally classified as instrument transformers. Generally instrument transformers are…
Advantages & Disadvantages of Synchronous Motors
In industries induction motors are employed mostly because of less cost, rugged construction, good starting torques and very less maintenance. Synchronous motors are rarely used in industries for drive applications.…
Advantages & Disadvantages Electromagnetic Relays
In Electromagnetic relays operating current flows through the coil. When this operating current increases, coil energizes the electromagnet. When the operating current becomes large, the magnetic field produced by electromagnet…
Neutral Grounding Practice in Power System
Generally on neutral grounding is provided at each voltage. There will be several voltage levels between the generation of the power and distribution of the power in the power system.…
Shunt Capacitor Advantages in Power System
Normal loads on ac supply system are inductive in nature (eg: motors, power transformers, voltage regulators, induction furnace, choke coils, magnetic systems, discharge tubes etc) Inductive power requires reactive power…
Crowbar fault protection circuit
Crowbar circuit is used to protect circuit or equipment under fault condition Over Current Causes: Over current flow through thyristors in a circuit due to: Flow of short circuit current…
R R-C Firing Circuits Disadvantages
Firing Circuits: Gate triggering is the most commonly used turn-on method employed to switch on the thyristors. Triggering circuits is also called firing circuits. There are various firing circuits available.…
Importance of Hysteresis Loop
Hysteresis Loss: When a magnetic material is subjected to a cycle of magnetization (magnetized first in one direction and later magnetized in opposite direction in a cyclic manner), an energy…
Advantages of Star and Delta Systems
In a 3-phase system the alternators or generators may be star connected or delta connected. Likewise 3-phase loads may be star connected or delta connected. Some of the advantages of star and…
Generator Protection Interview Questions & Answers
Synchronous Generator Protection Interview Questions Answers What are the common types of generator faults? The common types of faults occurring in synchronous generators are: Stator winding faults (phase to phase…
