# What is a three phase connection?

What is a three phase connection?

RYB, 440 volt/phase

## Related questions

Description : Explain MCB and ELCB with connection diagram supplying single phase load.

Last Answer : OR OR Explanation: * MCB provides short circuit protection. * MCB provides overload protection * ELCB provides earth fault protection. * MCB is in series with ... occurs, the ELCB cuts off the power within the time of 0.1 sec. automatically to protect the personnel.

Description : Write the relation between phase and line current, phase and line voltage for Star connection.

Last Answer : Line voltage is equal to root three times of phase voltage and line and phase currents are equal in star connection

Description : THREE PHASE INDUCTION MOTORS MCQ

Last Answer : 101. Insertion of resistance in the stator of an induction motor (a) increases the load torque (b) decreases the starting torque (c) increases the starting torque (d) none of the above Ans: b

Description : List different starting methods of three phase synchronous motor. Explain any one of them.

Last Answer : Different Starting Methods of Three Phase Synchronous Motor: As synchronous motor is not self starting, different methods of starting are as follows: 1) By using an Induction (Pony) motor 2) ... . The rotor gets pulled into synchronism and starts running at constant speed as a synchronous motor.

Description : Why is a capacitor used in a single phase motor and not in three phase motor ?

Last Answer : In 1-phase induction motor capacitor work is generate the auxiliary winding current than excite the main winding to rotor starts rotate. After rotor start rotating about 75% of their speed than auxiliary ... emf to start the motor.so,in 3-phase induction motor is self start induction motor.

Description : Why is a three phase denoted by R, Y, B ?

Last Answer : phase 1 ,R =Red colour cable terminal, phase 2 Y=Yellow colour terminal cable,Phase 3 B=Blue colour cable terminal, N =Neutral. For identification.

Description : State any four advantages of three phase induction motor.

Description : Define balanced and unbalanced load in three phase circuit.

Last Answer : Balanced Load: When all the imedances of 3 phases are equal in magnitude and of same nature then load is said to be balanced.  Unbalanced Load: When all the imedances of 3 phases are not equal in magnitude and of different nature then load is said to be unbalanced.

Description : State any four applications of three phase circuits.

Last Answer : The application of three phase circuits are 1. Three phase circuit is used for power transmission over long distances. 2. Three phase circuit can produce rotating magnetic field 3. Three phase ... three phase Motors and Transformers. 4. Three phase circuit is used for power converters circuits.

Description : State advantages of three phase over single phase.

Last Answer : Advantages of 3-phase system over 1-phase system: -  1. More output: For the same size, output of poly-phase machines is always higher than single phase machines.  2. Smaller size: For ... are self- starting: The three phase ac motors are self starting, while single phase induction motor are not.

Description : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is

Last Answer : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is 4 percent

Description : When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is (A) 86.6% (B) 50% (C) 57.7% (D) 73.2%

Last Answer : When a V-V three phase transformer system is converted into a Δ-Δ system, increase in capacity of the system is 73.2%

Description : In a three-phase supply floating neutral is undesirable because it way give rise to?

Last Answer : In a three-phase supply floating neutral is undesirable because it way give rise to unequal line voltages across the load.

Description : Three phase synchronous motor will have how many sliprings?

Last Answer : Three phase synchronous motor will have two sliprings.

Description : How is a three phase cage induction motor self starting?

Last Answer : Any type of induction motor is self starting. Because the reason for torqe production require two flux displaced by some angle theta.If theta is constant with time then torqe will be constant;if ... torqe also pulsating. In induction motor this angle theta is not pulsating.so it is self starting

Description : Explain three phase half wave controller or three phase unidirectional controller.

Last Answer : Three phase half wave controller or unidirectional controller:

Description : Explain Three Phase Bidirectional Delta Connected Controller.

Last Answer : Three Phase Bidirectional Delta Connected Controller:

Description : What is mean by plugging in three phase induction motor?

Last Answer : Plugging in three-phase induction motor means interchanging of any two phases of a stator for quick stopping.

Description : Explain three phase bridge inverter.

Last Answer : Three phase bridge inverter: Three phase bridge inverter converts DC voltage input to three-phase variable frequency variable voltage output. DC voltage source can be a DC source or output of the rectifier. ... in proper sequence. The switch may be thyristor or IGBT etc.

Description : Explain three phase full wave controller.

Last Answer : Three phase full wave controller: Three phase full wave controller is also called as the three-phase bidirectional controller. Let the load is star connected so at each phase there are antiparallel connected SCRs. ... conduct at the same time and the third phase will be open.

Description : three phase to single phase cycloconverter

Last Answer : three phase to single phase cycloconverter

Description : how can we reverse the direction of rotation of three phase induction motor ?

Last Answer : The direction of rotation of three phase induction motor can be reversed by plugging i.e by changing any two out of three phases of the supply to the stator of the Induction motor terminal.

Description : What is difference between Star and Delta Connection?

Last Answer : Star is        1. Open ckt       2. At center point present  neutral   Delta is     1.   Closed ckt 2.      Neutral not present in this case

Description : What is the voltage in 3 phase line?

Last Answer : between 430 to 440 v

Description : Explain with the neat circuit diagram only the scott connection scheme for conversion of three phase supply to two phase supply. Name one application of the same.

Last Answer : Three-phase to Two-phase Transformation (Scott Connection of Transformers): Working: i) Scott connection can be used for three-phase to two-phase conversion using two single-phase transformers ... a 3-phase system with a two-phase system with the flow of power in either direction.

Description : Which of the following 3-phase connection of a transformer causes interference with the neighbouring communication lines:  (A) Delta-Star (B) Star-Delta (C) Delta-Delta (D) Star-Star

Last Answer : Which of the following 3-phase connection of a transformer causes interference with the neighbouring communication lines: Star-Star

Description : UPS- How to give Connection?

Last Answer : Ans. Means Uninterrupted power supply. To give UPS connection, first normal supply is kept off. Then, loads of essential and non essential are to be segregated. Essential loads are to be brought under single point of control. Then, UPS can be connected.

Description : State functions of ; i) Cable box ii) Guard wire iii) Shackle insulator iv) Stay wire used in service connection

Last Answer : i) Function of Cable box: To hold and inspect incoming and outgoing terminals  ii) Function of Guard wire : A grounded conductor placed beneath an overhead transmission line in order to ground ... in service connection: To give mechanical Support to pole, line and prevent leakage current if any

Description : Why underground service connections are service connections are costly than overhead service connection

Last Answer : Reason: Underground service connection is given by underground cable. This cable is costly than bare conductor. Sometimes cable trench is required for cable laying, which requires additional cost. So underground service connections are costly than overhead service connection.

Description : Define service connection and state types connection and state types of overhead service connection

Last Answer : Service Connection:- It is the input conductor or wire which is carried out from supply company (authorities) pole to consumers' main board or premises. Types of overhead service ...  1. Overhead service connection with Bare conductor 2. Overhead service connection with weather proof cable

Description : State the principle of solar cell. What is necessity of series and parallel connection of solar cells.

Last Answer : Principle of solar cell:-  Working:- Solar cell operates on principle of Photo-voltaic effect Solar cell works in following steps:  The solar cell is composed of a P-type ... of Voltage & Current rating it is necessity of connecting series and parallel connection of solar cells.

Description : State necessity of series connection and parallel connection of batteries.

Last Answer : Necessity of series connection of batteries: 1. The batteries are available with some specific terminal voltages. e. g. 6V, 12V, 24V, 48V etc. 2. If we want to have some terminal voltage other than ... batteries of capacities I1, I2, I3, I4 . are connected in parallel, all having identical emfs.

Description : Compare star and Delta Connection.

Last Answer : Compare Star and Delta connected system:  Star connected system Delta connected system   In STAR connection, the starting or finishing ends (Similar ends) of three coils are connected together to form the ... VPH Line Current is √3 times of Phase Current. i.e. IL = √3 IPH

Description : Which of the following connection of transformers will give highest value of secondary voltage ? (A) Delta primary delta secondary (B) Delta primary star secondary (C) Star primary star secondary (D) Star primary delta secondary

Last Answer : Which of the following connection of transformers will give highest value of secondary voltage ? (A) Delta primary delta secondary (B) Delta primary star secondary (C) Star primary star secondary (D) Star primary delta secondary

Last Answer : Direction of rotation of a split phase motor can be reversed by reversing the connection of either running winding or starting winding.

Description : How different are people really?

Last Answer : On a universal level we are all one, as we are one with every organism, all created “equal” in natures grand design. On a “personal” level we are vastly different in how our nature/nurture/cultural dichotomies show up. Sooo…the usual double edged sword.

Description : Do you find yourself feeling a special bond with certain others on Fluther?

Last Answer : Definitely although I hate to be cliquey. There are some who you just have an affinity for and an ease with. and those with superior intelligence who agree with me

Description : How do I open gaming ports on my Belkin router?

Last Answer : is there a thing called DMZ on the website. under a tab named application & gaming?

Description : Consider a circuit with three parallel branches connected across a DC supply. What is the ratio of the branch currents I1 : I2 : I3 if the branch resistances are in the ratio of 2 : 3 : 4 respectively? A) 2 : 3 : 4 B) 6 : 4 : 3 C) 4 : 3 : 2 D) None of these

Last Answer : Consider a circuit with three parallel branches connected across a DC supply. What is the ratio of the branch currents I1 : I2 : I3 if the branch resistances are in the ratio of 2 : 3 : 4 respectively? A) 2 : 3 : 4 B) 6 : 4 : 3 C) 4 : 3 : 2 D) None of these

Description : When three resistors with unequal values are connected in parallel, _______ A) The current across the resistors is the same  B) The voltage drop across the resistors is the same C) The voltage drops across the resistors is proportional to the resistance of each resistor D) None of these

Last Answer : When three resistors with unequal values are connected in parallel, The voltage drop across the resistors is the same

Last Answer : Three point starter can be used for both shunt and compound motor.

Last Answer : A three point starter is considered suitable for shunt as well as compound motors.

Description : what is the difference between four point starter and three point starter?

Last Answer : The shunt connection in four point starter is provided separately form the line where as in three point starter it is connected with line which is the drawback in three point starter.

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.

Last Answer : In case one phase of a three-phase synchronous motor is short-circuited the motor will not start.

Description : speed control methods of three phase induction motor?

Last Answer : Speed control of three phase induction motor

Description : SINGLE PHASE INDUCTION MOTORS MCQ

Last Answer : 101. After the starting winding of a single phase induction motor is disconnected from supply, it continues to run only on (a) running winding (b) rotor winding (c) field winding (d) compensating winding Ans: a ... motor is usually reduced by using (a) gearing (b) belts (c) brakes (d) chains Ans: a

Description : How to Build a Static 3 Phase Converter

Last Answer : How to Build a Static 3 Phase Converter Static 3 phase converters enable offices and residents to conserve energy efficiently. In fact, electricity is available in 3 power phases, which enables ... converter and the necessary appliances that are needed in building the main and the remote appliances.

Description : Draw single phase full wave mid-point converter for inductive load. Draw input and output waveforms for it.

Last Answer : Circuit Diagram: Waveforms:

Description : State classification of Phase controlled rectifiers.

Last Answer : Classification of phase controlled rectifiers: