Tirril Voltage Regulator: In this type of Tirril Voltage Regulator, a fixed resistance is cut in and cut out of the exciter field circuit of the alternator. This is achieved by rapidly opening and closing…
Active and Passive Satellite: Active and Passive Satellite - Possible communication satellites may be active or passive and the major difference between the two is that whether the communication relay involves passive reflection or an…
Kelvins Bridge and Kelvins Double Bridge: When the resistance to be measured is of the order of magnitude of bridge contact and lead resistance, a modified form of Wheatstone's bridge, the Kelvins Bridge is employed.…
Current Chopping: When interrupting small inductive currents such as transformer excitation currents, circuit breakers tend to clear before the natural current zero is reached. This is because the low-current ionized conducting path may become prematurely…
Induction Type Directional Power Relay: This Induction Type Directional Power Relay operates when power in the circuit flows in a specific direction Unlike a non-directional overcurrent relay, a directional power relay is so designed that…
What is Diode Transistor Logic (DTL) Circuit? Diode Transistor Logic (DTL) is also a saturated logic and uses diodes, resistors and transisÂtors. The circuit diagram is shown in Fig. 47.2. The baÂsic DTL logic circuit…
Loss of Excitation Protection in Generator: Loss of excitation protection in generator can endanger the generator or the connected system or both. It is caused by accidental tripping of field breaker, short circuit in the…
Automatic Combustion Control System: Automatic Combustion Control System is very popular nowadays and this has been developed mainly to maintain load against demand, to prevent smoke, to increase boiler house efficiencies, to carry out routine…
External Fault Backup Protection for Generators: Overcurrent and earth fault protection is provided for backup protection of large sized (above 1 MVA) generators protected by differential protection against external phase-to-phase faults and earth faults. The…
Reflection of Electromagnetic Waves by a Conducting Surface: In view of the way in which signals propagate in waveguides, it is now necessary to consider what happens to Reflection of Electromagnetic Waves when they encounter…
