Answer / tathagata

If single phase motor is supplied by ac supply, it will rotet
because single phase motor are universal motor. So it work
for both AC & DC.

But the DC supply must be less than its AC rating, because
in DC there is no reactant .

I=V/(R+jX) (AC)

I=V/R (DC)


So current is vary high which may burnt out the winding.

Answer / santosh

torque in single phase induction motor is produced due to rotating magnetic field. if this motor is fed from dc, the rotating magnetic field is absent and the machine will not run.
also in the absence of reactance in DC, the machine will try to draw high current which will damage the winding.

Answer / alan jenkins

In a nutshell it depends what type of motor it is, some motors with a wound rotor and brushgear will run on AC and DC, however AC induction motors will not rotate, the DC current will have a locking effect on the rotor, hence DC injection braking (anyone heard of that ?)leaving a DC current on these motors for any length of time will heat up the windings.

one split ac how can told of this ac which Tr tell me us

0 Answers   Wipro,

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what happen if the supply is given to the stator of the 3phase induction motor with out assembling the rotor ?

0 Answers  

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what material used made for the resistance,for the purpose of zero temperature coefficient?

2 Answers  

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as ac supply is given 2 the transformer why it doesnot depends upon powerfactor????

2 Answers  

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what sis the testing procedure of transformer and ht panel?

1 Answers  

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what is the meaning of improving the power factor (give technical ans not therotical)

2 Answers  

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what will happen while giving 2 phase supply to 3 phase motor

5 Answers  

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why transformer rating in kva

6 Answers  

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why voltage between neutral and earth, with out secondary grounded distribution transformer

1 Answers   Wescosa,

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1 HP = how many Kva

5 Answers  

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what is the difference between electrical and electronic choke?

0 Answers   TCS,

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We have drive feeding an output contactor for a 5000 hp motor @ 5kV application. The motor FLA is 629amps x 1.25% service factor = 786.25 amps The cable that we current have in place between the drive and the output contactor is 350kcmil- MV-105 (parallel cables). Per the NEC table 310.60 (C) (69). This show the cable ampacity is at 615 amps per cable for a rating of 1230 amps. We have derated the cable for the cable tray and the multiple cables application and our calculations show that after the correction factor factor we are at 922amps. 1230 amps x .75% correction factor factor = 922.5 amps. The customer is driving us to then use another safety factor of .25% off of the already derated cable. Can you please provide a longhand calculation for your solution on this application?

0 Answers   Siemens,

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