In Swinburne's Test on D.C.machines, why the efficiency is
more when the machine runs as generator than when it runs as
motor???
Answers were Sorted based on User's Feedback
Answer / lakshmi devadas
The total loss Pl= constant loss(Pk) + variable loss(Pv)
for any DC machine.
For generator, since Ia=Il+If, the efficiency = 1-Pl/
(VtIl+Pl)
For motor, Ia=Il-If , the efficiency =1-Pl/VtIf.
Its obvious that the efficiency value for generator will be
higher than motor, since Pl is not a negligible value.
Is This Answer Correct ? | 56 Yes | 11 No |
Answer / dharani
because of high currents obtained when it is placed as motor &
Is This Answer Correct ? | 68 Yes | 29 No |
Answer / hema
in motor the supply voltage isopposed by the back emf .soit
draws more current to run the load
but in generator the whole generated emf supplied to the load
Is This Answer Correct ? | 35 Yes | 9 No |
Answer / chaitanya
the output of a generator is more and also the input to the generator will be less and so the efficiency will b more
Is This Answer Correct ? | 31 Yes | 16 No |
Answer / m.divya sree
machine is to be run as motor under no load condition by requiring less power to be drawn from supply so the efficiency of generator is more than motor
Is This Answer Correct ? | 6 Yes | 5 No |
Answer / n.dinakar
Swinburne's test is the most commonly used and simplest method of testing of shunt and compound wound DC machines which have constant flux. In this test the efficiency of the machine at any load is pre-determined. We can run the machine as a motor or as a generator.
Is This Answer Correct ? | 1 Yes | 3 No |
how to calculate the settings for shaft ct protn in hydro generators
I try to check the three phase voltage in multimeter, in 125A isolator switch incommer. first i touch R phase, and then i touch Y phase using multimeter, the moment i touched, it blasts and that moment i got blindness. multimeter selector position is correct(750V AC MODE AND RED PROBE WASS IN v AND BLACK PROBE WASS IN COM. MODE. COULD ANYBODY GIVE ANSWER FOR THIS TO AVOID FURTHER ACCIDENTS PLEASE?
2. A current i=(10+10 sin t)amperes is passed through MI type ammeter. its reading will be.........
what is power factor
why ceiling fan give hising sound
what is the working principle of a DG Set, Alternator, & exiter
how we identify between current transformer and potential transformer without having it name plate?
what is interpose vt where it is used and y it is used?
Ps Explain YWY,AFWY Type Cable
What is the drawback of class b amplifier? How is this minimized?
why incomer bay is required before transformer bay if there are more than 1 nos. of transformer bay.
Pure inductive ckt takes power from AC when 1. Applied voltage and Current increases 2. applied voltage and current decreses 3. voltage decreases and current decreases please justify