In a dynamometer 3-phase power factor meter, the planes of the two moving coils are at?

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Answer :

In a dynamometer 3-phase power factor meter, the planes of the two moving coils are at 120°.

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Related questions

With a neat sketch explain working of 1 phase dynamometer type power factor meter.

Description : With a neat sketch explain working of 1 phase dynamometer type power factor meter.

Last Answer : Working of 1 phase dynamometer type power factor meter : The current coil is connected in series with load. Two pressure coils marked as A and B are connected across the supply terminals ... becomes stationary and the pointer shows steady deflection corresponding to the power factor of the load. 

In a single phase power factor meter the phase difference between the currents in the two pressure coils is?

Last Answer : In a single phase power factor meter the phase difference between the currents in the two pressure coils is exactly 90°.

The two pressure coils of a single phase power factor meter have?

Last Answer : The two pressure coils of a single phase power factor meter have the same dimensions and the same number of turns.

A power factor meter has?

Last Answer : A power factor meter has one current circuit and two pressure circuits.

What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016

Description : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

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The resistance in the circuit of the moving coil of a dynamometer wattmeter should be?

Last Answer : The resistance in the circuit of the moving coil of a dynamometer wattmeter should be high.

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Last Answer : Working : Initially the switch S is kept at position 1.The attenuator gets excluded and the bridge T network is adjusted for full suppression of fundamental frequency and hence we get ... is obtained on the meter.Thus the total rms distortion is indicated by the reading of attenuator. 

A dynamometer wattmeter can be used for?

Last Answer : A dynamometer wattmeter can be used for both D.C. and A.C.

The power factor of a single phase load can be calculated if the instruments available are?

Last Answer : The power factor of a single phase load can be calculated if the instruments available are three ammeters or three voltmeters.

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is

Description : The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is (A) 11% (B) 9% (C) 1.1% (D) 3%

Last Answer : The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is 11%

In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero...

Description : In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero. The power factor of the load must be?

Last Answer : In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero. The power factor of the load must be 0.5.

In a 3-phase power measurement by two wattmeter method, both the wattmeters had identical readings...

Description : In a 3-phase power measurement by two wattmeter method, both the watt meters had identical readings. The power factor of the load was?

Last Answer : In a 3-phase power measurement by two wattmeter method, both the watt meters had identical readings. The power factor of the load was unity.

In a low power factor wattmeter the compensating coil is connected?

Last Answer : In a low power factor wattmeter the compensating coil is connected in series with pressure coil.

In a low power factor wattmeter the pressure coil is connected?

Last Answer : In a low power factor wattmeter the pressure coil is connected to the load side of the current coil.

In a Weston frequency meter, the magnetic axes of the two fixed coils are?

Last Answer : In a Weston frequency meter, the magnetic axes of the two fixed coils are perpendicular.

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Description : State the effects of errors in dynamometer type wattmeter due to i) pc- inductance ii) pc- capacitance iii) mutual inductance iv) Connection.

Last Answer : Errors in wattmeter:  i) pc - inductance: Pressure coil inductance causes wattmeter to read more power than actual .  ii) pc-capacitance: The wattmeter reads less power.  iii) ... iv) Connection: In uncompensated wattmeter , the reading of wattmeter includes the powerloss in coils. 

State any four errors that occur in dynamometer type wattmeter

Description : State any four errors that occur in dynamometer type wattmeter

Last Answer : Errors that occur in dynamometer type wattmeter: 1. Errors due to method of connection. 2. Error due to pressure coil inductance. 3. Error due to pressure coil Capacitance. 4. Error due to mutual ... Error due to eddy currents. 7. Temperature error. 8. Error due to vibration of moving system

With neat diagram explain constructional details of dynamometer type wattmeter.

Description : With neat diagram explain constructional details of dynamometer type wattmeter.

Last Answer : Working Principle of Wattmeter: It consists of two stationary coils, called current coils and one moving coil, called voltage or potential coil. The moving coil is mounted on the spindle, in the gap ... experiences a force and tends to move in the direction as per Fleming's left hand rule. 

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.

In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?

Description : In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?

Last Answer : In an alternator, at lagging power factor the generated voltage per phase as compared to that at unity power factor must be more than terminal voltage.

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What is meant by Power factor?

Description : What is meant by Power factor?

Last Answer : Ans. Power factor means ratio of true power to apparent power. It is cosine of phase angle between voltage and current. Its value is 1 for Unity P.F. Loads, 0 to 1 lagging for inductive loads and o to 1 leading for capacitive loads.

State the effects of low power factor on efficiency and voltage regulation of short transmission lines.

Description : State the effects of low power factor on efficiency and voltage regulation of short transmission lines. 

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Briefly explain how the power factor of an inductive circuit can be improved.

Description : Briefly explain how the power factor of an inductive circuit can be improved.

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Why capacitors are used to improve power factor?

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.

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Last Answer : Power factor tariff results into energy conservation: i) Applying incentives and penalties according to power factor is an effective way, which enables consumer to improve power factor so that he can ... finally leads to reduction in the current drawn by the load and helps for energy conservation.

Draw and explain bulk correction method for power factor & control.

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A transformer has negative voltage regulation when its load power factor is

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Last Answer : 0

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Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW

Description : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is  (1) 122.8 GWh (2) 198.55 GWh (3) 128.2 GWh (4) 188.82 GWh

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Description : In a synchronous generator delivering lagging power factor load  (1) the excitation emf leads terminal voltage by the power angle (2) the excitation emf lags terminal voltage by the power angle (3) ... by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle

Last Answer : In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle

The benefit of power factor correction in a power system is

Description : The benefit of power factor correction in a power system is (A) lower power consumption (B) increased demand charge (C) reduced load carrying capabilities in existing lines (D) reduced voltage profile

Last Answer : The benefit of power factor correction in a power system is lower power consumption

The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu

Description : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are (A) 0.5 pu ... pu, 0.5 pu (C) 0.707 pu, 0.707 pu (D) 0.5 pu, 0.5 pu

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The power factor of a D.C. circuit is always?

Description : The power factor of a D.C. circuit is always?

Last Answer : The power factor of a D.C. circuit is always unity.

The ratio of active power to apparent power is known as____ factor.

Description : The ratio of active power to apparent power is known as____ factor.

Last Answer : The ratio of active power to apparent power is known as power factor.

The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is?

Description : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is?

Last Answer : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is 32 kW.

Power factor of electric bulb is?

Description : Power factor of electric bulb is?

Last Answer : Power factor of electric bulb is unity.

The power factor at resonance in R-L- C parallel circuit is?

Description : The power factor at resonance in R-L- C parallel circuit is?

Last Answer : since a rlc circuit at resonance behaves like a pure resistive circuit, i.e there is no phase difference between current and voltage, hence the power factor is unity.

Power factor of the system is kept high?

Description : Power factor of the system is kept high?

Last Answer : Power factor of the system is kept high to reduce line losses, to maximise the utilization of the capacities of generators, lines and transformers, to reduce voltage regulation of the line.

Power factor of an inductive circuit is usually improved by connecting capacitor to it in?

Description : Power factor of an inductive circuit is usually improved by connecting capacitor to it in?

Last Answer : Power factor of an inductive circuit is usually improved by connecting capacitor to it in parallel.

Capacitors for power factor correction are rated in?

Description : Capacitors for power factor correction are rated in?

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

Poor power factor?

Description : Poor power factor?

Last Answer : Poor power factor reduces load handling capability of electrical system, results in more power losses in the electrical system, overloads alternators, transformers and distribution lines, results in more voltage drop in the line.

Power factor of an electrical circuit is equal to?

Description : Power factor of an electrical circuit is equal to?

Last Answer : Power factor of an electrical circuit is equal to R/Z, cosine of phase angle difference between current and voltage, kW/kVA.

When a D.C. series motor is connected to A.C. supply, the power factor will be low because of?

Last Answer : When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.

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.

The standard full-load power factor ratings for synchronous motors are?

Last Answer : The standard full-load power factor ratings for synchronous motors are unity or 0.8 leading.

For power factor correction, synchronous motors operate at?

Last Answer : For power factor correction, synchronous motors operate at no-load and greatly over-excited fields.