What is Phase sequence indicator?

What is Phase sequence indicator?
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1 Answer

Answer :

Phase sequence indicator used to indicate the 3-phase direction- comes in two styles; Lights and meters. In the lighted variety, a sequence of light goes on for the phase sequence being read, while the meter indicates which phase direction it is reading. 
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Related questions

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Describe with neat diagram phase sequence indicator.

Description : Describe with neat diagram phase sequence indicator.

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Last Answer : Answer: C

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Last Answer : Answer: B

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Last Answer : Answer: B

The direction of propeller shaft rotation in a turbo-electric synchronous propulsion drive motor is changed by reversing the _____________. A. polarity of the propulsion motor B. polarity of the propulsion generator C. phase sequence of power to the motor D. phase sequence of power to the generator

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Last Answer : Answer: C

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Last Answer : Answer: A

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Last Answer : Answer: B

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Description : What will happen if transformer in parallel connection have different phase sequence ?

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Description : What is phase sequence?

Last Answer : The sequence of attaining the maximum value of the induced emf in each set of winding among those three sets is known as phase sequence. This phase sequence is usually indicated by the letters R, Y, B.

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Description : Explain negative phase sequence protection of alternator.

Last Answer : Negative phase sequence protection of alternator: Unbalanced loading on alternator mainly causes the negative sequence currents which generate the negative sequence components of magnetic fields. These fields ... components due to unbalance and operates the relay which further operates CB.

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Description : Draw sinusoidal waveform of 3 phase emf and indicate the phase sequence.

Last Answer : Phase sequence is R-Y-B.

What is Phase sequence? Draw waveforms of 3 phase emf.

Description : What is Phase sequence? Draw waveforms of 3 phase emf.

Last Answer : Phase sequence: It is the order in which the three phases reach their peak or maximum values. It is shown in below fig. the phase sequence is A-B-C (or R-Y-B). In the following waveforms, it is ... 120º, B- phase voltage attains its positive maximum value. So the phase sequence is R-Y-B. 

Define phase sequence of three phase supply with waveforms.

Description : Define phase sequence of three phase supply with waveforms. What is normal phase sequence? Which 3 standard colours are used to denote the phase sequence?

Last Answer : It  is  sunnosoidal  sequence.

The sequence components of current of a single-phase load connected to a 3-phase system are

Description : 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

Last Answer : The sequence components of current of a single-phase load connected to a 3-phase system are equal positive, negative and zero sequence components

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Description : In a dc-ac 3-phase MOSFET bridge inverter circuit, the switches are marked in a sequence as 1, 2, 3 in the top-half and 4, 5, 6 in the bottom half of the bridge. The triggering sequence of switches that gives balanced output voltage is (A) 1 ... 3, 4, 2, 6 (C) 1, 6, 2, 4, 3, 5 (D) 1, 4, 2, 5, 3, 6

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The phase sequence of a three-phase alternator will reverse if ...

Description : The phase sequence of a three-phase alternator will reverse if  A) The field current is reversed keeping the direction of rotation same. B) The field current remains the same but the direction of ... The field current is reversed and also the direction of rotation is reversed D) None of the above

Last Answer : The phase sequence of a three-phase alternator will reverse if The field current remains the same but the direction of rotation is reversed 

An alternator has a phase sequence of RYB for its phase voltage. In case...

Description : An alternator has a phase sequence of RYB for its phase voltage. In case the direction of rotation of alternator is reversed, the phase sequence will become?

Last Answer : An alternator has a phase sequence of RYB for its phase voltage. In case the direction of rotation of alternator is reversed, the phase sequence will become RBY.

What are the advantages of sequence control of ac voltage regulators?

Description : What are the advantages of sequence control of ac voltage regulators?

Last Answer : a. System power factor is improved. b. Harmonics are reduced in the source current and the load voltage.

What is meant by sequence control of ac voltage regulators?

Description : What is meant by sequence control of ac voltage regulators?

Last Answer : It means that the stages of voltage controllers in parallel triggered in a proper sequence one after the other so as to obtain a variable output with low harmonic content.

Define negative sequence component.

Description : Define negative sequence component.

Last Answer : It has 3 vectors equal in magnitude and displaced from each other by an angle 120 degrees and has the phase sequence in opposite to its original phasors.

Define zero sequence component.

Description : Define zero sequence component.

Last Answer : They has 3 vectors having equal magnitudes and displaced from each other by an angle zero degrees.

Define positive sequence component.

Description : Define positive sequence component.

Last Answer : -has 3 vectors equal in magnitude and displaced from each other by an angle 120 degrees and having the phase sequence as original vectors.

State the three sequence components.

Description : State the three sequence components.

Last Answer : Positive sequence components, negative sequence components and zero sequence components.

What is meant by positive, negative and zero sequence reactance.

Description : What is meant by positive, negative and zero sequence reactance.

Last Answer : The reactance diagram of a power system, when formed using positive, negative and zero sequence reactances are called positive, negative and zero sequence reactance diagram resp.

What is meant by positive, negative and zero sequence impedance.

Description : What is meant by positive, negative and zero sequence impedance.

Last Answer : The impedance of the circuit element for positive, negative and zero sequence component currents are called positive, negative and zero sequence impedances resp.

What are sequence impedance and sequence networks?

Description : What are sequence impedance and sequence networks?

Last Answer : The sequence impedances are the impedances offered by the devices for the like sequrnce component of the current. The single phase equivalent circuit of a power system consists of impedances to current of any one sequence is called sequence network

What are zero sequence components?

Description : What are zero sequence components?

Last Answer : The zero sequence components of a three phase unbalanced vectors consists of 3 vectors of equal magnitude and with zero phase displacement from each other.

What are negative sequence components?

Description : What are negative sequence components?

Last Answer : The negative sequence components of a three phase unbalanced vectors consists of three vectors of equal magnitude displaced from each other by 120 degree in phase and having the phase sequence opposite to that of the original vectors.

What are positive sequence components?

Description : What are positive sequence components?

Last Answer : The positive sequence components of a three phase unbalanced vectors consists of three vectors of equal magnatude, displased from each other by 120 in phase and having the same phase sequence as the original vectors.

When the Zero sequence reactance arises?

Description : When the Zero sequence reactance arises? 

Last Answer : If a machine is operating with an earthed neutral, a system earth fault will give rise to zero sequence current in the machine. 

When the negative sequence reactance arises?

Description : When the negative sequence reactance arises?

Last Answer : Negative sequence arises whenever there is any unbalance present in the system. Their effect is to set up a field rotating in opposite direction to the main field.

What is Sequence control?

Description : What is Sequence control?

Last Answer : The control of separate motors to operate in a predetermined pattern. 

What is Zero sequence reactance?

Description : What is Zero sequence reactance? 

Last Answer : If a machine is operating with an earthed neutral, a system earth fault will give rise to zero sequence current in the machine. 

What is Negative sequence reactance?

Description : What is Negative sequence reactance?

Last Answer : Negative sequence can arise whenever there is any unbalance present in the system. Their effect is to setup a field rotating in opposite direction to the main field.