Electrical Engineering Interview Questions

Photo diodes

Why can't the photo diodes produce large amperes of current? Are there any large photo diodes producing current more than milli amps??

Regarding three phase supply

Why 440 volt 3 -phase power supply is showing neutral as phase and phase as no supply? As still the power is supplied to the load and its working?

Model of a transmission line

What is the standard size of a model of an electric tower for lab exhibition?

Direction of current flow in three pole regulator

The circuit diagram is at http://avstop.Com/ac/apgeneral/regulation.Html I cant completely figure out the way current is flowing through the three pole regulator that I have attached. I believe that current is coming up through the l1 coil into the positive terminal of the armature. And, I think current...

Track gauge

What is the purpose of track gauge used in transformers?

What is wind velocity in heat exchagers?

Why we need OOPS for electrical engineering?

Co axial in guided media

If the cables of co axial breaks down through connections then can it connect again...? Give reason..

Why we need OOPS for electrical engineering ?

Cable fault identification.

One 3.5c cable is connected in a feeder with the neutral is isolated in the two ends(3 phases connected and neutral open in both sides). Now on rear end the output voltage is getting reduced by 20v in two phases and 40v increased by another phase.(between phase and neutral but neutral in open in two...

Relation between mutual flux , useful flux & power factor of a transformer.

If mutual flux is 1.2 wb, power factor if 0.8 lag, then what is the useful flux of a transformer?

Stator resistance range

What is the range of the stator resistance of 3 phase induction motor?

PF card function

A powerplant has 8 gensets operating in grid parallel mode. In one genset sometimes there is PF variation and kvar variation. The plant operates in PF mode. When this variation is observed the load is stable, voltage is also stable, freq and genset speed is also stable. How will you check the functioning...

Transformer reactive power

Though transformer consist winding which usually cause reactive power change in both generator and motor but it wont affect reactive power passing through transformer why?

Range of the stator resistance

What is the range of the stator resistance of 3 phase induction motor? To calculate losses for the motors with kw rating of 4, 7.5, 11, 15, 30, 37, 40, 45, 55, 90 etc. On which parameters it does depends on?

Zero powerfactor method of voltage regulation

Why we do not use pure capative load instead of pure inductive load?

Em waves

When the operating wavelength of line is λ/4

Power lines

In an AC transmission line(3 phase), if there is a short between any two phases. How will you determine this fault on a protection relay. What will your wave forms look like?

Nanotech applications

Name some of the application of nanotech in field of power enggineering.

Life of earthing copper rods

What is the maximum life of earthing copper rods in earthing ground system?