Engineering Job Interview-How to face them successfully: C.S.Roy, Digital Power Corporation.

My subject is electronics, so I intend to provide guidance to the job seekers in electronics and allied industries. The freshers from other disciplines (e.g. Civil, Electrical, Mechanical and Computer Science engineering) also are supposed to be benefited by this article.

    

Before anything, please keep it in mind that Electronics is a very fast developing branch of engineering where the technology of today may get obsolete tomorrow! Thus, you must have sound knowledge about the current technologies, of course, that does not mean that the lack of knowledge about classical electronics will be accepted by your employers. Here are some concrete examples of abysmal poor performance of majority of the students of several polytechnics of rural areas.

     The questions were on very basic segments of electronics and were very much related to the needs of contemporary industry, unfortunately enough, most of the students failed to answer the following basic questions:

1.     Draw a simple full wave unregulated power supply circuit (Less than 1% of the group could answer it!).

2.     If AC mains voltage is 230V AC- Is it RMS or PEAK Voltage? (Some 40% said this to be RMS only 10% of them could calculate the Peak value! Some multiplied the RMS by √3 while others divided the same by √2!)

3.     What is power factor? What are the problems of low power loads? (Majority about 70% answered it by saying “This is cosΦ” Some wrote the equation P = I V cosΦ. A tiny minority about 5% could answer both the above questions because most of them had very little idea about the physical significance of the term-power factor).

4.     Draw the diagram of an OP-Amp based voltage comparator circuit and show at least one example of a comparator circuit application (Approximately 30% could not draw the symbol of OP-Amp correctly, 40% did not know what was the voltage comparator and 95% could not site a single example of “Application of comparator circuit”!).

5.     Draw a voltage regulator circuit with a specification of 5V, 500mA (Surprisingly 60% of the students could not understand the proper meaning of the term “Voltage Regulator”, rest struggled hard to draw something with zener diode, resistors, etc but attempts failed due to incomplete knowledge. None of them knew that the easiest modern solution was the three terminal regulator 7805 I.C.!).

6.     What could be the electric bill per day in INR of a 1 ton AC operated for 8 hours, assuming 7 INR/unit? (This question was asked to final year electrical, electronics & mechanical engineering (diploma) students).

Approximate right answer is something like 67 Rupees/day.

Out of 95 participants of the interview, only 2 delivered the nearest correct answer! Others quoted the figures ranging from Rs 400 to Rs 2000 per day!!!

Upon investigation, the following points came out:

      The interview participants did not know the following simple facts:-

v What is the power needed by the 1ton air conditioner (Approx 3.504 Kilo Watt, 12000 Btu.)

v Many of them simply forgot that 1 unit = 1KWh of electrical energy!

About 30% of the students appeared have almost zero knowledge about the basic physics (work, power & energy). They could not calculate at all or offered absurd answer.

1.     What is the “energy star” rating of modern air conditioners and other electrical appliances mean? (This question was asked by a leading consumer electrical appliance OEM in an interview participated by hundreds of diploma & degree electrical, mechanical engineers. Surprisingly & unfortunately enough, only 1% of the participants of the interview could offer answer that could make sense! Many of them said “energy star indicates those appliances which consume huge amount of energy”! They did not know that “energy star” has very much to do with the efficiency of electrical appliances).

2.     What are the problems of fossil fuel generated power? What are alternate energy sources? A solar (PV) panel generates AC or DC Voltage? What is the normal electrical energy storage device used in solar electricity generation system? What are the unit of Battery capacity and solar panels? What is the typical (rough figure) energy efficiency of a solar panel? What is MPPT solar charging system? What are stand alone & grid tied renewable energy system? What are the role of a solar charge controller?

While the above mentioned questions appear unfamiliar to the participants of many traditional campus interview programmes, such types of questions will be asked increasingly by many upcoming alternate energy companies (including WEBEL solar, Suzolon Energy, EMC, and GP Tronics).

       Such giant companies execute turnkey projects on solar/wind power generation (up to 500MW capacity) employing hundreds of electronics, electrical and mechanical engineers both diploma and degree level.

     

Thus, above discussion clearly shows that in most of the engineering interviews, very fundamental knowledge of the respective subject are needed to be successful.

  

Hence, it is strongly advised that before appearing in technical interviews, candidates should refresh their knowledge about basic aspects of their disciplines. The basic knowledge includes also the smatter of physics, chemistry and mathematics.

Best wishes to all the students who are appearing in the upcoming interviews.