Power-factor of industrial arc and induction furnace is:

Power-factor of industrial arc and induction furnace is:
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1 Answer

Answer :

Power-factor of industrial arc and induction furnace is: very low lagging

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Related questions

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Description : The supply for arc welding is : 

Last Answer : The supply for arc welding is : Low voltage, high current ac or dc voltage

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Description : For induction heating, which of the following is abnormally high?  A)Voltage B) Current C) Frequency D) Phase angle

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Description : The range of frequencies used in induction heating is :  (A) 0-25 Hz  (C) less than 200 Hz  (B) 50 to 100 Hz  (D) more than 1 kHz

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Last Answer : (B) 400 - 700

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Description : In a 100 TPD Sponge Iron plant, the sponge iron is fed to the Induction melting furnace,  producing molten steel at 88% yield. The Energy consumption details are as follows: Coal Consumption : 130 ... molten  steel (product). 3. Total Energy Consumption of Plant in Tons of Oil Equivalent (TOE )

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Last Answer : (C) electric resistance heating

State any two applications of each for the following types of electrical heating : (i) Direct resistance heating(ii) Indirect induction heating (iii) Direct.arc heating (iv) Dielectric heating

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Last Answer : (i) Direct resistance heating:- 1. This type of heating used for industrial purpose 2. Salt bath heating: This utilized for the purpose of carbonizing, tempering, quenching and hardening of steel tools 3. ... purpose. 14)In foundry for heating of sand, core, which are used in molding processes.

When using multiple SAW arc systems (twin wires etc), the arcs often have different polarities or use all AC rather than DC polarity, this is to? a) Prevent arc blow between arcs b) To maximize productivity c) To even out the power factor on the mains supply d) Make it easier to initiate the arc

Description : When using multiple SAW arc systems (twin wires etc), the arcs often have different polarities or use all AC rather than DC polarity, this is to? a) Prevent arc blow between arcs b) To maximize productivity c) To even out the power factor on the mains supply d) Make it easier to initiate the arc

Last Answer : a) Prevent arc blow between arcs

In low or standard frequency induction furnace, heat is produced by the (A) Combination of induced current and skin effect (B) Induction and resistance (C) Current flow through a heating element (D) None of these

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Last Answer : (B) Induction and resistance

The amount of combustible escaping unconsumed from the furnace, depends upon the (A) Air supplied and furnace temperature (B) Burner design (thoroughness of mixing versus stratification) (C) Air preheat and the flow of gases in the furnace (mixing by induction, by acceleration or by change of direction) (D) All (A), (B) and (C)

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Last Answer : (D) All (A), (B) and (C)

In the heating process of the ________type a simple method of temperature control is possible by means of a special alloy which loses its magnetic properties at a particular high temperature and regains them when cooled to a temperature below this value. (A) Indirect induction over (B) core type induction furnace (C) coreless induction furnace (D) high frequency eddy current

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Differentiate between core type and core less induction furnace.

Description : Differentiate between core type and core less induction furnace.

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Explain with neat diagram construction and working of Ajax Wyatt vertical core induction furnace.

Description : Explain with neat diagram construction and working of Ajax Wyatt vertical core induction furnace.

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Fuel economy in an industrial furnace operation cannot be achieved by the use of (A) Stoichiometric combustion air (B) Non-preheated combustion air (C) Combustion air not enriched with oxygen (D) Recuperators

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Power in the wind is proportional to

Description : Power in the wind is proportional to

Last Answer : Power in the wind is proportional to (Wind velocity)3

Power for lighting in passanger coach, in a long distance electric train, is provided?

Last Answer : Power for lighting in passanger coach, in a long distance electric train, is provided through individual generator of bogie and batteries.

Overhead lines for power supply to tramcars are at a minimum height of?

Last Answer : Overhead lines for power supply to tramcars are at a minimum height of 10 m.

In case of locomotives the tractive power is provided by?

Last Answer : In case of locomotives the tractive power is provided by double cylinder, double acting steam engine.

In a steam locomotive electric power is provided through?

Last Answer : In a steam locomotive electric power is provided through small turbo-generator.

A three-phase, squirrel cage, induction motor will run hot due to a/an ______________. A. improper brush position B. reversed commutating pole C. shorted stator D. high power factor

Description : A three-phase, squirrel cage, induction motor will run hot due to a/an ______________. A. improper brush position B. reversed commutating pole C. shorted stator D. high power factor

Last Answer : Answer: C

A three-phase, squirrel cage, induction motor will run hot due to _____________. A. open stator coils B. high power factor C. dirty or corroded slip rings D. reversed commutating poles

Description : A three-phase, squirrel cage, induction motor will run hot due to _____________. A. open stator coils B. high power factor C. dirty or corroded slip rings D. reversed commutating poles

Last Answer : Answer: A

The air gap provided in induction motors should be checked periodically with a feeler gage to detect an unequal air gap and _____________. A. decreased motor magnetizing current B. hysteresis loses C. increased power factor D. mechanical damage to the rotor

Description : The air gap provided in induction motors should be checked periodically with a feeler gage to detect an unequal air gap and _____________. A. decreased motor magnetizing current B. hysteresis loses C. increased power factor D. mechanical damage to the rotor

Last Answer : Answer: D

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

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

why single-phase induction motor has low power factor?

Description : why single-phase induction motor has low power factor?

Last Answer : The current through the running winding lags behind the supply voltage by a very large angle. Therefore power factor is very low.

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

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.

What is the effect of increased load on power factor of induction motor?

Description : What is the effect of increased load on power factor of induction motor?

Last Answer : Power factor of an induction motor increases with loading.

In an induction machine, if the air gap increased a) Speed will be reduced b) Efficiency will be improved c) Power factor will be lowered d) Breakdown torque will be reduced

Description : In an induction machine, if the air gap increased a) Speed will be reduced b) Efficiency will be improved c) Power factor will be lowered d) Breakdown torque will be reduced

Last Answer : Ans: Power factor will be lowered

A three phase induction motor is drawing 16 Ampere at 440 Volts. If the operating power factor of the motor is 0.90 and the motor efficiency is 92%, then the mechanical shaft power output of the motor is a) 12.04 kW b) 10.09 kW c) 10.97 kW d) None of the above

Description : A three phase induction motor is drawing 16 Ampere at 440 Volts. If the operating power factor of the motor is 0.90 and the motor efficiency is 92%, then the mechanical shaft power output of the motor is a) 12.04 kW b) 10.09 kW c) 10.97 kW d) None of the above

Last Answer : b) 10.09 kW

The power factor of a squirrel cage induction motor is (A) low at light load only. (B) low at heavy load only. (C) low at light and heavy load both. (D) low at rated load only.

Description : The power factor of a squirrel cage induction motor is (A) low at light load only. (B) low at heavy load only. (C) low at light and heavy load both. (D) low at rated load only.

Last Answer : (A) low at light load only.

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

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

In induction motors, the length of air gap in kept as small as mechanically possible is order to have (a) low power factor (b) high power factor (c) high over load capacity (d) any of the above

Description : In induction motors, the length of air gap in kept as small as mechanically possible is order to have (a) low power factor (b) high power factor (c) high over load capacity (d) any of the above

Last Answer : (b) high power factor

The type of single-phase induction motor having the highest power factor at full load is

Description : The type of single-phase induction motor having the highest power factor at full load is (A) shaded pole type (B) split-phase type (C) capacitor-start type (D) capacitor-run type

Last Answer : The type of single-phase induction motor having the highest power factor at full load is capacitor-run type

A 400 V, 50 Hz 30 hp, three-phase induction motor is drawing 50 A current at 0.8 power factor lagging.

Description : A 400 V, 50 Hz 30 hp, three-phase induction motor is drawing 50 A current at 0.8 power factor lagging. The stator and rotor copper losses are 1.5 kW and 900 W respectively. The friction and windage losses are 1050 W and the ... the motor will be (A) 23.06 kW (B) 24.11 kW (C) 25.01 kW (D) 26.21 kW

Last Answer : A 400 V, 50 Hz 30 hp, three-phase induction motor is drawing 50 A current at 0.8 power factor lagging. The stator and rotor copper losses are 1.5 kW and 900 W respectively. The friction and windage losses are 1050 W and the core losses are 1200 W. The air-gap power of the motor will be 25.01 kW

The power factor of an induction motor under no load conditions will be close to

Description : The power factor of an induction motor under no load conditions will be close to (A) 0.2 lagging (B) 0.2 leading (C) 0.5 lagging (D) Unity

Last Answer : The power factor of an induction motor under no load conditions will be close to 0.2 lagging

The power factor of a single-phase induction motor is usually?

Last Answer : The power factor of a single-phase induction motor is usually lagging.

A synchronous motor has better power factor as compared to that of an equivalent induction motor...

Description : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?

Last Answer : A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because stator supply is not required to produce magnetic field.

An induction motor has relatively high power factor at?

Last Answer : An induction motor has relatively high power factor at near full load.

At which time power factor of the induction motor is low?

Description : At which time power factor of the induction motor is low?

Last Answer : The power factor of the inducction motor is low at the time of starting as compare to while the induction motor is running.