Can you help by answering this question?

Why is electromagnetism so important?

11 views
in Electrical Engineering by
Two wattmeter method is employed to measure power in a 3 -phase balanced system with the current coil connected in the A and C lines. The phase sequence is ABC. If the wattmeter with its current coil in A -phase line reads zero, then the power factor of the 3 -phase load will be

1 Answer

0 votes
by

Two wattmeter method is employed to measure power in a 3 -phase balanced system with the current coil connected in the A and C lines. The phase sequence is ABC. If the wattmeter with its current coil in A -phase line reads zero, then the power factor of the 3 -phase load will be 0.5 lagging.

Related questions

1 answer 27 views

Two wattmeters are used to measure the power in a 3 -phase balanced system. What is the power factor of the load when one wattmeter reads twice the other ?  (a) 0 (b) 0.5 (c) 0.866 (d) 1

asked Apr 23, 2018 in Electrical Engineering by Zeeshan
0 answers 9 views

Two wattmeter method can be used in a three phase system excited with balanced three phase supply  A) To measure real power and power factor in a balanced load B) To measure reactive power in a balanced load C) To measure real power in an unbalanced load D) All of the above 

asked Apr 9, 2018 in Electrical Engineering by Zeeshan
1 answer 18 views

 In the measurement of power of balanced load by two wattmeter method in a 3-phase circuit, The readings of the wattmeters are 4 kW and 2 kW respectively, the later is being taken after reversing the connections of current coil. the power factor and reactive power of the load is A) 0.2 & 6 kVAR B) 0.2 & 6 √3 kVAR C) 0.32 & 2 kVAR D) 0.32 & 2 √3 kVAR

asked Jun 17, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 12 views

The minimum number of wattmeter(s) required to measure 3-phase, 3-wire balanced or unbalanced power is  A) 1 B) 2 C) 3 D) 4

asked May 20, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 23 views

The power consumed by a balanced 3-ph load is measured by two-wattmeter method. The meter readings are 8 kW and 4 kW. The power factor of the load is (A) zero (B) 0.5 (C) between zero and 0.5 (D) between 0.5 and unity

asked Apr 28, 2018 in Network Analysis by Shimroz123
1 answer 24 views

In a balanced 3 -phase 200 V circuit, the line current is 115.5 A. When the power is measured by two wattmeter method, one of the wattmeters reads 20 kW and the other one reads zero. What is the power factor of the load ?

asked Apr 23, 2018 in Electrical Engineering by Zeeshan
1 answer 15 views

Measurement of power and power factor of a 3-phase system by two wattmeter method can be obtained in case of  1. Balanced load and balanced source  2. Balanced source with 3-phase 3-wire unbalanced load  3. Unbalanced source with 3-phase 3-wire balanced load  4. Balanced source with 3-phase 4-wire unbalanced load  5. unbalanced and unbalanced source    (a) 1 only (b) 2, 3 and 5 (c) 1, 2, 3, 4 and 5 (d) 1, 2, 3 and 5 

asked May 13, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 22 views

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?

asked Mar 21, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 133 views

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

asked Mar 21, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 7 views

Two wattmeters connected to measure the power input to a balanced three-phase circuit indicate 4.5 KW and 3 KW respectively. Find the power factor of the circuit. A. 0.7 B. 0.8 C. 0.95 D. 0 

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
0 answers 21 views

In the measurement of three phase power by two wattmeter method, if the two wattmeter readings are equal then power factor of the circuit is  (A) 0.8 lag (B) Unity (C) 0.8 lead (D) Zero 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 13 views

In a three-phase system, when the loads are perfectly balanced, the value of neutral current is equal to: A. Zero B. One-third of the maximum value C. Two -third of the maximum value D. The maximum value

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
1 answer 73 views

State any two disadvantages of one wattmeter method of measurement of 3 phase power.

asked Sep 6, 2018 by Shimroz123
0 answers 18 views

While measuring power in a three phase load by two wattmeter method, the reading of two wattmeter are equal and opposite, when (a) load is balanced (b) power factor is unity (c) phase angle is between 60° to 90° (d) the load is purely inductive 

asked May 26, 2018 in Electrical Measurements and Instrumentation by Shimroz123
0 answers 38 views

A balanced Delta connected load supplied with 440 V 50 Hz three phase AC supply has R=10 Ohm and L=0.6 mH in is each arm. Calculate line and phase current, active power.

asked Aug 12, 2018 in Basic electrical and electronics engineering by Quiz
1 answer 12 views

Power (P) in a 3 phase circuit with two watt meters at unity power factor is (W1 & W2 = watt meter readings)

asked May 15, 2018 in Electrical Engineering by Shimroz123
1 answer 223 views

Total instantaneous power supplied by a 3-phase ac supply to a balanced R-L load is

asked Apr 28, 2018 in Electrical Engineering by Shimroz123
0 answers 16 views

The current coil of a wattmeter is connected to the C.T. of R phase. Its potential coil is connected across Y & B phases. The wattmeter measures (a) active power in R phase (b) active power of Y-phase (c) reactive power in R-phase (d) power proportional to 3-phase power if the load is balanced 

asked May 25, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 16 views

The current coil of a wattmeter is connected to the CT of R-phase. The potential coil is connected across Y and B phases. The wattmeter measures

asked Mar 28, 2018 in Electrical Measurements and Instrumentation by Shimroz123
0 answers 45 views

For a balanced three phase star connected load for which line voltage is 230V and per phase resistance and reactance is 6 Ohm and 8 Ohm respectively. Calculate: 1) phase voltage 2) line current 3) power factor 4) total power absorbed

asked Aug 12, 2018 in Basic electrical and electronics engineering by Quiz
1 answer 21 views

At a particular instant, the R-phase voltage of a balanced 3-phase system is + 30 V, and the Y-phase voltage is – 90 V. The voltage of B-phase at that instant is (A) + 120 V (B) – 120 V (C) – 60 V (D) + 60 V

asked Apr 25, 2018 in Electrical Engineering by Shimroz123
1 answer 15 views

In two -wattmeter method of power measurement, if one wattmeter shows negative reading, then the power factor of the circuit is treated as (A) Unity (B) Lagging (C) Leading (D) Zero

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
1 answer 11 views

For power measurement of three phase circuit by two wattmeter method, when the value of power factor is less than 0.5 lagging:

asked May 22, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 18 views

A moving coil meter has a resistance of 3 Ω and gives full scale deflection with 30 mA. To measure voltage up to 300 V, the external resistance to be connected in series with the instrument is (A) 9997 Ω (B) 10000 Ω (C) 997 Ω (D) 10003 Ω

asked Apr 28, 2018 in Power Electronic Controlled Drives by Shimroz123
0 answers 19 views

Two 3-phase synchronous generators with reactance 60% and 40% feed a fault current of 1200 A up to short-circuit fault point. The short-circuit current is (A) 1200 A (B) 2400 A (C) 4000 A (D) 5000 A 

asked Jun 4, 2018 in Synchronous machine by Shimroz123
1 answer 34 views

A balanced three-phase, 50 Hz voltage is applied to a 3 phase, 4 pole, induction motor. When the motor is delivering rated output, the slip is found to be 0.05. The speed of the rotor m.m.f. relative to the rotor structure is: (A) 1500 r.p.m. (B) 1425 r.p.m. (C) 25 r.p.m. (D) 75 r.p.m

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 11 views

In a 3 phase, 4 wire unbalanced System, the current in the neutral wire is 18 A. The magnitude of the zero sequence current is

asked May 12, 2018 in Electrical Engineering by Shimroz123
1 answer 13 views

In case of a 3-phase short-circuit fault in a system, the power fed into the system is   (a) Mostly reactive (b) Reactive only (c) Mostly active (d) Active and Reactive both equal 

asked May 13, 2018 in Electrical Engineering by Shimroz123
1 answer 14 views

In the measurement of power by two wattmeter method, when the readings of the two wattmeters are equal, the power factor is (A) Zero (B) Leading (C) Lagging (D) Unity

asked May 12, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 31 views

A alternator is delivering power to a balanced load at unit power factor. The phase angle between the line voltage and the line current is? (A) 90° (B) 60° (C) 30° (D) 0° 

asked Apr 23, 2018 in Electrical Engineering by Shimroz123
1 answer 18 views

Three equal impedances are first connected in delta across a 3 -phase balanced supply. If the same impedances are connected in star across the same supply then,

asked Apr 23, 2018 in Electrical Engineering by Zeeshan
0 answers 14 views

Pick up the false statement from the choices given below : (A) In a 3 -ph balanced delta circuit, phase voltage is same as line voltage (B) In a 3 -ph balanced delta circuit, phase current is same as line current (C) In a 3 -ph balanced star circuit, line voltage is 1.73 times phase voltage (D) In a 3 -ph balanced star circuit, phase current is same as line current 

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
1 answer 8 views

A two-phase generator is connected to two 90Ω load resistors. Each coil generates 120 V ac. The value of current flowing through the common neutral line will be: A. 1.33 A B. 1.88 A C. 2.66 A D. 1.77 A

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
0 answers 70 views

The power in a 3-phase load is measured by two watt meters. If one watt meter reads zero, then the load power factor is (A) Zero (B) 0.5 (C ) 0.866 (D) unity 

asked Jun 4, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 283 views

The sequence components of current of a single-phase load connected to a 3-phase system are (A) equal positive and negative sequence components (B) equal positive, negative and zero sequence components (C) vector sum of sequence currents is zero (D) algebraic sum of sequence currents is zero

asked Apr 28, 2018 in Power system by Shimroz123
1 answer 17 views

The power delivered to a 3-phase load can be measured by the use of two wattmeters only when the  (a) load is unbalanced (b) load is balanced (c) three phase load is connected to the source through three wires (d) three phase load is connected to the source through four wires

asked May 13, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 20 views

Describe with neat circuit diagram the method of measurement of power in a High voltage, high current a.c circuit.

asked Sep 15, 2018 by Shimroz123
1 answer 16 views

The power delivered to a three-phase load can be measured by the use of 2 wattmeter only when the A. Load is balanced B. 3 -phase load is connected to the source through 3 wires C. Load is unbalanced D. 3 -phase load is connected to the source through 4 wires

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
1 answer 10 views

 In dynamometer type of wattmeter, which of the coil is split up into two parts?

asked May 29, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 16 views

The line current in a balanced delta system is 30 A. The load current is (A) 30√3 A (B) 30/√3 A (C) 10 A (D) 30/√2 A

asked Apr 28, 2018 in Network Analysis by Shimroz123
0 answers 22 views

If two 3-phase transformers with unequal voltage ratios are connected in parallel, the result is (A) circulating current on no-load (B) no circulating current on no-load (C) dead short-circuit (D) equal no-load secondary emfs 

asked Jun 4, 2018 in Electrical Machine by Shimroz123
0 answers 16 views

A dynamometer type wattmeter with its voltage coil connected across the load side of instrument reads 250 W. If the load voltage be 200 V, what power is being taken by load? The voltage coil has resistance of 2000 Ω. (1) 200 W (2) 215W (3) 230 W /(4) 245 W

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 13 views

The line trap unit employed in carrier current relaying method offers: (A) high impedance to 50 Hz power frequency signal (B) high impedance to carrier frequency signal (C) low impedance to carrier frequency signal (D) high impedance to 50 Hz power frequency signal and high impedance to carrier frequency signal

asked Apr 11, 2018 in Computer Engineering by Shimroz123
1 answer 28 views

The maximum possible power of a 3-phase synchronous motor with synchronous reactance 0.8 p.u. connected to a bus-bar of 1.0 p.u. and excitation adjusted to 1.2 p.u. is (A) 0.5 p.u. (B) 0.96 p.u. (C) 1.5 p.u. (D) 1.8 p.u.

asked Apr 25, 2018 in Electrical Engineering by Shimroz123

Welcome to electronics2electrical.com here you can ask questions related to electrical, electronics, mechanical, telecommunication, instrumentation, computer, mathematics, physics etc.
Be respectful to all the members. Do not copy and paste the answers from other websites which have copyright content. While asking question give full details about it.

Categories

Most popular tags

power motor dc circuit transformer voltage current used system phase resistance factor synchronous load ac energy induction electric generator series frequency between speed capacitor use electrical meter line difference control type mosfet transmission magnetic plant high single instrument bjt unit source advantages function diode and machine winding field define torque parallel amplifier supply shunt thyristor motors electricity arduino maximum time relay armature problem value on transformers types coil diagram state flow ratio material three formula starting direction theorem method emf operating efficiency digital wave microprocessor test instruments inductance loss measure operation connected signal low applications effect single-phase network temperature working constant losses different law wattmeter measuring compare controlled breaker drive device logic rc full switch flux wire resistivity disadvantages free of materials machines angle force converter conductor transistor gain open protection scr core measurement number bridge principle generators reactance circuits negative the friction iron loop short pole battery conservation steam resistors hysteresis computer using analog lines secondary station gate a rectifier inverter linear induced relays nuclear capacitance basic characteristics design direct work rotor electronics ammeter forces diesel damping rlc connection factors capacitors minimum insulation moving regulation running self systems air fault range main stability quality starter igbt eddy alternator ideal rl average 3-phase plants arc thermal error fuzzy biasing dielectric pressure balanced superposition errors copper rotation feedback impedance measured electronic electrons charge inductive transfer explain start off back curve over solar is three-phase tariff locomotive peak bias zener engineering commutator surge conductors rating universal potentiometer density permanent mechanical transducer capacity memory adc excitation two fuse pure harmonics application semiconductor inductor internal pmmc reaction welding resonance traction permeability breakers rms designed electromagnetic si generation brushes switching capacitive shaded rate 1 distribution resistor methods delta star oscillator reluctance simplification algebra 8085 boolean weston dynamometer insulating strength installation definition fuel heating earth units

8,450 questions

7,047 answers

132 comments

3,085 users

...