what is principle of DC machines?
Answer Posted / vishal ingle
DC machines are broadly of two types viz Motor or generator.
Both works on the principle of electomagnetic induction.
Generator:- Due to relative motion between magnetic flux
and winding, an emf is induced in it.
Motor: Due to the current flowing through the winding and
magnetic field flux, a force is experienced by the
conductor.
| Is This Answer Correct ? | 11 Yes | 1 No |
Post New Answer View All Answers
what is the necessary of using inductance property in transmission lines even through resistance is used to opposes the high current flows in that?????
i need mat lab program to find out the transmission line losses,regulation and losses
1- XC and the RC time constant are both measures of the reaction of C to a change in ____? 2-The power factor is a numerical ratio with a value between 0 and 1 equal to the ______________ of the phase angle. 3-When V and I are out of phase because of reactance, the product of V times I is called ______________ power 4-For _____________ inductors, the branch currents can be added algebraically. 5- The ______________ power in watts can be calculated as I^2R 6-Calculate XL with L = 30mH and f = 1kHz ( I have Xl=2piFL 2*3.141592653*1kHz*30mH =188 ohms Please check) 7-A parallel RL circuit has the values, R = 5kohms, XL = 5kohms. A voltage source of Vt = 10Vrms is connected in parallel to R and L. Determine the total current, It delivered by the voltage source Vt. 8-A series RC circuit has R = 1Mohm and C = 1microF. How long would it take for the capacitor to fully discharge if it is initially fully charged? 9-A circuit has real power = 300W and an apparent power of 500VA. Determine the power factor and phase angle. 10-The time constant for an LR series circuit is T = 0.1s and R = 10ohms. Calculate the inductance L.
An 8 pole, 50 Hz, 3-phase IM is loaded to a poing where pull out torque will occur. The rotor resistance per phase is 0.3 ohm and motor stalls at 650 rpm. The rotor reactance at stand still is A 2 ohm B 1.25 ohm C 3.15 ohm D 2.25 ohm
WHY MOSTLY Rph IS USED FOR CONTROL CIRCUITS AUX. SUPPLY ?
Write down the design procedure of commutaj.
Is there chopping current in resistive circuit
I have a relay contact rated at 220v dc which is supplied with a 24vdc from the panel,for it to trip the dampers(24vdc).What if the application of the relay changes so that it should work at its rated 220vdc then will it work at 24vdc supply given or any other consideration needs to be taken .....
Can we use BS 6651 and BS EN 62305 standards for computer room lightning ptotection in substation?
What are the functions of temperature scanner in power transformer?
Explain bypass capacitor?
what is the effect of change in supply frequency on load angle of synchronous motor,all other parameters remaining same?
please explain to me how to calculate current,voltage,resistance with formula??
Is any generator is developed which is operated with out diesal or other expensive source?
i want some interview related questions with their answers which can help for attend the interviews...