Electrical Engineering Interview Questions

what is the method of electric earth for the protection of low voltage electric equipment

3364

WHERE to use CVT & PT.

22880

how can calculated the rating of the 11 KV transformer?

NBCC,

6585

Why do we have 110V, 230V, 415V etc. in electrical transmissions? Why not 100V, 200V,400V?

7730

how circuit breaker work.. what is the operations taking place inside a circuit breaker when an overcurrent occurs... is it similar to fuse?

LTT,

799

how many earthing is required for sever room?

4180

What is GIS Substation and how it operate? where these type of substation installed?

27435

HOW many type of Circut Breaker in the world used in 400 kv substation?

15616

What is difference between earth leakage relay and restricted earth fault relay ?

33694

why synchronous motor has zero starting ?

NTPC,

13864

how to find out capacitor range?

3031

what happens when d cexcitation given to alternator is removed while it is running or what happens when dc excitation is failed in alternator while running?

14472

why we are calculating the capacitance between phase(conductor line)and ground in transmission line?why cant we calculate capacitance between the phase and the nuetral line?if so what is procedure.

1396

what is the difference between VARIAC,AUTO TRANSFORMER,DIMMERSTAT.

22279

hi all i like to know vat is power plot in control systems also i want to know abt latest trends in electrical & electronics

738

Un-Answered Questions { Electrical Engineering }

what is 30-phase of transformer

767

need to make a report. Need to choose a 3phase induction motor. Load conditions motor will operate in : Maximum Load: 30 Kw Speed: 2950 rpm Ambient temp: 20 cent Supply voltage: 440V Frequency: 50Hz need to look for the safety factor when choosing the motor, went through catalouge found a few, but dont know how to choose the safety factor allowing an extra load something above 30 KW to avoid any harm.

622

difference between a diode and thyristor?

965

what are the assumptions made in swineburne's test?

832

What is the difference between diesel generator engine with and without turbo charger with the same capacity?

457

why +24 v and -48 v give to BTS? If -48v protect from surge then why we not use -24 v?

679

What is power distribution criteria for converting single phase unbalanced residential load to 3 phase star connected balance system. Does total KW converted to 3 Phase. Means Divided by root 3.

876

why the perameters of secondary circuit are more important then that of the primary circuit of induction motor?

539

what is the diference between the 4pole & 6pole DC Motors & what is advantage 6pole over the 4pole ?

663

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819

I have one ct of ratio 3000-2000/1 Amp its knee point voltage mentioned on name plate is 500-333/30mA-50mA at Vk/2. in secondary box there is three terminal named 1S1, 1S2, 1S3 then on which terminal obtained the knee point voltage ie 1S1-1S2 OR 1S1-1S3 & also specify the knee point voltage for the ratio 3000 from name plate.

1087

How to select batteries required for ups and the inverter if we Known load? And how AH is selected of battery?

165

Can anyone explain me about the RLC based Impulse high voltage generator and how to and operation of Series resonant High voltage reactor...?

657

What are the factors influence the choice of an electrc drive?

767

What is the purpose of stand by earth fault protection for transformer ?

761