In order to improve the power factor ___ device is employed in the substation a) Synchronous condenser b) Synchronous reactor c) Series Capacitors d) None of the above

1 Answer

Answer :

Ans: A

Related questions

Description : Which of the device is employed in substation to limit the short circuit current in the power system: a) Shunt condenser b) Reactor c) Series capacitor d) Shunt capacitor

Last Answer : Ans: B

Last Answer : In a distribution system, in order to improve power factor, the synchronous capacitors are installed at the receiving end.

Description : Can a synchronous condenser improve power factor?

Last Answer : Yes, synchronous condenser can improve power factor.

Description : In a substation the following equipment is not installed (a) exciters (b) series capacitors (c) shunt reactors (d) voltatre transformers

Last Answer : (a) exciters

Description : Capacitors can be used in electric distribution systems to improve power factor. This is accomplished by seesawing energy between the capacitor and the _____________. A. generator B. inductive loads C. resistive loads D. all of the above

Last Answer : Answer: B

Description : In order to reduce the harmful effects of harmonics on the A.C. side of a high voltage D.C. transmission system ______are provided. (A) synchronous condensers (B) shunt capacitors (C) shunt filters (D) static compensators

Last Answer : Ans: C Xc= 1/ ωc

Description : Why capacitors are used to improve power factor?

Last Answer :  Capacitors generate reactive power instead of that drawn from source which is required by inductive loads.so it reduce the reactive current which is drawn from source to be drawn from capacitor.This control in Electric bills cost.

Description : What is synchronous Condenser? Where and why it is used?

Last Answer : An overexcited synchronous motor running at no- load and used for power-factor correction is called synchronous condenser. It is also called synchronous capacitor. It is used in a large system where the use of static capacitor is inefficient and expensive. It is used for power-factor correction.

Description : What is meant by synchronous condenser?

Last Answer : An over excited synchronous motor running on no load is known as synchronous condenser. It is used to improve the power factor of the system.

Description : How the synchronous motor can be used as s synchronous condenser?

Last Answer : Synchronous motor is operated on over excitation so as to draw leading reactive current and power from the supply lines. This compensates the lagging current and power requirement of the load making ... to become unity. The motor does the job of capacitors and hence called as synchronous condenser.

Description : Distinguish between synchronous phase modifier and synchronous condenser

Last Answer : A synchronous motor used to change the power factor or power factor in the supply lines is called synchronous phase modifier. A synchronous motor operated at no load with over excitation condition to draw large leading reactive current and power is called a synchronous condenser.

Description : What is synchronous condenser?

Last Answer : An over-excited synchronous motor under no load , used for the improvement of power factor is called as synchronous condenser because, like a capacitor it takes a leading current.

Description : What is synchronous condenser or phase advancer?

Last Answer : An over excited synchronous motor takes leading current just like a condenser and gives leading power factor. A synchronous motor, which I used only for the purpose of improving power factor, can be called as synchronous condenser or phase advancer.

Description : Series capacitors are used to (a) compensate for line inductive reactance (b) compensate for line capacitive reactance (c) improve line voltage (d) none of the above

Last Answer : (a) compensate for line inductive reactance

Description : When the capacitors of a Wein Bridge are replaced by inductors, the bridge becomes ___

Last Answer : Wein Inductance Bridge

Description : A device used in an electrical circuit to change alternating current to direct current, is known as a _____________. A. current transformer B. rectifier C. condenser D. shunt

Last Answer : Answer: B

Description : The voltage drop, for constant voltage transmission is compensated by installing (a) inductors (b) capacitors (c) synchronous motors (d) all of above (e) none of the above

Last Answer : (c) synchronous motors

Description : A three-phase alternator is operating at 450 volts with the switchboard ammeter indicating 300 amps. The kw meter currently indicates 163.6 KW, with a power factor of 0.7. If the power factor increases to 0.8, the KW meter reading would increase by ___ A. 17.8 KW B. 23.2 KW C. 30.6 KW D. 37.8 KW

Last Answer : Answer: B

Description : Stones are provided in the substation to: a) To avoid fire accident by draining oil from transformer if leaks b) To avoid growing of weeds and plants c) To provide insulation d) All the above

Last Answer : Ans: D

Description : What is the first equipment of the substation connected to the incoming transmission line?

Last Answer : Lightning arrestor is the first equipment of the substation connecting the incoming transmission lines. It protects other substation equipment from lightning and switching surges by suppressing them to ... between both the ends of major equipment such as power transformers for protection.

Description : What are different Bus bar materials used in Substation?

Last Answer : Busbars are generally made of copper and Aluminum. Aluminim has the advantage of one third the weight of the copper and also Aluminum requires less maintenance and proper use of alloys provide necessary rigidity required for bus material. Aluminum is used widely in EHV and HV stations

Description : What are the different electrical clearances in Substation?

Last Answer : Ground Clearance: This is the minimum distance between any live conductor and the earth or ground. Phase Clearance: It is the clearance between the different phases in a circuit or same phases in different ... The limits of work section may be ground or the platform on which the person is working.

Description : What are the different substation components

Last Answer : Circuit Breakers, Disconnecting switches, Grounding switches, Current Transformers, Potential Transformers or Capacitor voltage Transformers, Line Traps, Lightning Arrestors, Power Transformers, Shunt ... Station Buses and Insulators, Grounding system, Series capacitors and shunt capacitors.

Description : Locations where Gas Insulated Substation is preferred

Last Answer : Gas Insulated Substations are preferred in the places where land requirement for the substation is difficult such as in populated areas and highly polluted areas where outdoor switchyard is not ... pollution and saline environment. Under such case indoor GIS substation is very much helpful.

Description : What are different insulators used in substation

Last Answer : Different Insulators: Over head electrical conductors used for transmitting electric power is mostly bare and not covered with any insulation medium. The bare line conductors are ... Post insulators for support Stray arm insulators Shaft insulators Sectionalising insulators Connecting rod insulators

Description : The length cf air gap to be provided in ______ is primarily determined by power factor consideration. (a) d.c. series motor . (b) d.c. shunt motor (c) induction motor (d) synchronous motor

Last Answer : (c) induction motor

Description : What is Synchronous Condenser ?

Last Answer : When an over-excited synchronous motor is connected to a line to enhance the power factor without load , it is called a synchronous condenser.

Description : What is a synchronous condenser?

Last Answer : A synchronous condenser is a device identical to a synchronous motor, whose shaft is not connected to anything but spins freely. Its purpose is not to convert electric power to mechanical power or vice ... or absorb reactive power as needed to adjust the grid's voltage, or to improve power factor.

Description : Which of the following equipment, for regulating the voltage in distribution feeder, will be most economical ? (a) Static condenser (b) Synchronous condenser (c) Tap changing transformer (d) Booster transformer

Last Answer : (d) Booster transformer

Description : where the synchronous condenser are generally installed ?

Last Answer : the synchronous condenser are generally installed at receiving end side of transmission line 

Description : What is Synchronous condenser?

Last Answer : Synchronous condenser Big advantage of synchronous condenser is their large temporary overload capability and good harmonics performance. Synchronous condenser is ... ;voltage levels. Synchronous condenser have slow speed of response.

Description : The purpose of squirrel-cage windings in a synchronous motor is to ______________. A. provide more precise balancing B. produce a higher power factor C. eliminate arcing between the stator and the frame D. provide a means for starting

Last Answer : Answer: D

Description : The purpose of amortisseur windings in a synchronous motor is to ______________. A. reduce eddy current losses B. produce a higher power factor C. provide a means for starting D. eliminate arcing between the stator and the rotor

Last Answer : Answer: C

Description : Which of the following types of motors is often designed for use in correcting power factor? A. Polyphase B. Wound-rotor C. Induction D. Synchronous

Last Answer : Answer: D

Description : Amortisseur windings are installed in a synchronous motor to _____________. A. reduce eddy current losses B. produce a higher power factor C. provide a means for starting D. eliminate arcing between the stator and the rotor

Last Answer : Answer: C

Description : A synchronous motor is operating on no-load at unity power factor. If the field current is increased, power factor will become (A) Leading & current will decrease (B) Lagging & current will increase. (C) Lagging & current will decrease. (D) Leading & current will increase.

Last Answer : Ans: A Initially synchronous motor is operating at no load and unity power factor. When field current increases, the excitation will increase. Therefore, p.f will be leading and current will be I CosΦ < I

Description : ___ refers to all measures that can be taken directly within the website in order to improve its position in the search rankings.  A. On page optimization  B. Off page optimization  C. Both A and B  D. None of the above

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Description : In order to increase its range of measurement, a resistance would be placed in series with which of the following instruments? A. DC voltmeter B. DC ammeter C. frequency meter D. power factor meter

Last Answer : Answer: A

Description : Capacitors are used on the output of the power supply in today's consoles to _____________. A. filter out 'ripple' B. prevent overloads C. act as a permanent load D. decrease the average value of the output voltage

Last Answer : Answer: A

Description : Capacitors for power factor correction are rated in?

Last Answer : Capacitors for power factor correction are rated in kVAR.

Description : What type of electric motor is commonly used to start small auxiliary diesel engines? A. synchronous B. series C. shunt D. cage

Last Answer : Answer: B

Description : The speed-torque characteristics of a DC series motor are approximately similar to those of the _________motor. (A) universal (B) synchronous (C) DC shunt (D) two-phase

Last Answer : Ans: A Universal motor has same characteristics as DC series motor and also known as an a.c series motor.

Description : An electrical device which employs a stationary armature and a rotating electromagnetic field is used aboard ship as a ____________. A. magnetic amplifier B. ship's service alternator C. three-wire DC generator D. saturable core reactor

Last Answer : Answer: B

Description : In the illustration if the compressor fails to start but the condenser fan motor is running the problem is _______. EL-0042 A. no power between L1 and L2 B. the yellow wire is open at the freezer temperature control switch C. the overload is open D. the blue wire from the defrost heater is open

Last Answer : Answer: C

Description : In the illustration if the compressor fails to start but the condenser fan motor is running the problem is _______. EL-0043 A. no power between L1 and L2 B. the yellow wire is open at the freezer temperature control switch C. the overload is open D. the blue wire from the defrost heater is open

Last Answer : Answer: C

Description : List out the methods to improve the power factor of the induction motor.

Last Answer : The power factor of the induction motor can be improved by reducing the magnetizing current and leakage reactance. The magnetizing current can be reduced by reducing the length of air gap. The ... stator & rotor slots, by providing short chorded winding and reducing the overhang in stator winding.

Description : What is the proper procedure for suppressing electrical noise in a mobile station? A. Apply shielding and filtering where necessary B. Insulate a all plain sheet metal surfaces from each other C. ... -static spray liberally to all nonmetallic D. Install filter capacitors in series with all dc wiring

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Description : Heat flux through several resistances in series in analogous to the current flowing through several (A) Resistances in parallel (B) Capacitors in series (C) Resistances in series (D) None of these

Last Answer : (C) Resistances in series

Description : Find the total capacitances when two capacitors 2F and 5F are in series. a) 5/7 b) 12/7 c) 2/5 d) 10/7

Last Answer : d) 10/7

Description : In a full-wave voltage doubler, are the capacitors connected in series or in parallel with the output load?

Last Answer : In parallel.