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Theory - Practice - Experience: The Engineer's Power Triangle

As in all other fields of study, a good foundation is required. A poor foundation is like a poorly sharpened knife.


The choice of a career, most of the time, depends on one's talents and abilities evaluated and planned long before one graduates from his primary and secondary education.

All professional courses have to start with good foundation; andinstructors, professors and the schools do their best to impart these to students. Some schools do better; reason why employers, most of the time, prefer applicants coming - only - from prestigious schools where the quality of education is well known. But don't be intimidated, there are so many engineers who graduated from not so well known universities who were better engineers than colleagues who graduated top of their class from prestigious universities. Reason: They never stop studyingand learning after college.

Electrical Engineering as your chosen profession requires you to learn the basic scientific theories, facts and principles of electricity. You must be able to derive formulas used extensively in our practice and master symmetrical components: tools that will greatly simplify your analysis of unbalanced three phase power system. Fortunately for us, most of these commonly used electrical formulas do not even require us to use Differential or Integral Calculus. This, of course, is not the case if you are involved in the design of critical electrical or electronic components or circuitries.


Practice is simply using what you have learned in college. As a trainee or a novice, it gives you the chance to practice what you have learned. Take advantage of that opportunity and never be afraid to ask questions. What is unacceptable is pretending to ask a wise question on subjects you don't fully understand - yet. You might succeed on some, but sooner, your supervisor and your subordinates will discover your ignorance. Remember: A little knowledge is dangerous! Keep quiet and never be afraid to ask questions. Your supervisor and even your subordinate - who might not be an engineer, but a a very experienced Master Electrician - will understand you and might even go out of his way helping and assisting you. Humility is still one's best asset to learning.

Typical 230kV S/S 1-1/2 breaker scheme in a Ring Bus configuration where the number of breakers is same as the numbers of circuits

Top view of the above 230kV Breaker-and-a-half substation in Ring Bus configuration

Please take note the CT, PT and relays marked "same as the other side" are identical to what is shown at the bottom of the image to make the image height lesser.. The image was rotated 90 degrees, too. Download the Cad file at our Free Download page.



1. Experience is simply continuity of learning new things. As an example, your past project was just a simple 400/220Volts, 3Ph/1ph power supply system for a small industrial plant. Now, suddenly, you have a big industrial project that requires a 3ph, 34.5kV incomer, a 5MVA, 34.5/4.16kV transformer, a 4.16kV, 4-Bay Switchgear with the two bays of the switchgear reserved for the 2-4.16kV/400V/220 transformers and the fourth bay reserved as a tie breaker for a future project site.

You now find yourself challenged, a bit nervous and unsure of yourself; however, you know that your first move is how to configure the system. Take note of the transformer's winding configurations (wye-delta, wye-wye) since your instrument transformer connection configurations also depend on them. After you have a conceptual design you know that your next move would be to make some simple short circuit calculations; study medium voltage switchgears; study the system protection devices and their associated CTs and PTs, instrumentation and control for the system and, last but not the least, don't neglect the grounding system. Grounding system is sometimes referred to as electrical engineering's most neglected subject.

These tasks look daunting at first, but as you go along, probably in just less than three weeks or so, you will gain enough confidence to undergo the overall design of the system and gaining so much needed new experience.

2. Your new project might not be as big as the last one, but now your company asks you to prepare the bid drawings and the Technical Specification for your company's expansion project. Again you are at lost, but fear not! Writing Technical Specifications is much simpler than writing an essay. All you need is a good sample specification, downloadable from the sites of electrical equipment manufacturers for you to edit and serve your requirements. No worry, company engineering design sections usually have specifications specialists to check and edit your work and also the work of other disciplines (architectural, civil, mechanical) and combine them all together.


The Electrical Practitioners

Electrical Engineers and Master Electricians are licensed and regulated by various states to provide authorized professional services to the public. The word "engineer;" is defined as a person who passed the 5-year course in engineering and passed the strict government's professional regulating agency examination in order to guarantee his capability of providing safe and quality service to the public under the title "Engr." affixed before his name.

The word master in "Master Electrician;" on the other hand, means an electrician has passed the government licensing board which is based extensively on knowledge of electrical codes and established electrical installation safety practices, which are required, too in the Registered Electrical Engineer's examination.

The Electrical Engineering Examination in my country, and probably in other countries too, have three levels:

1. The Registered Electrical Engineer (REE)

He is the newly grad who passed the board examination. His practice of electrical engineering involves all aspects of electrical engineering. The registered engineer must have 5-years experienced "responsible character" before he could be qualified to take the Professional Electrical Engineer's (PEE) board exam. In my country, his application to take the PEE board exam must be signed and vouched by a PEE.

REEs, too are allowed to sign and seal electrical drawings to a limited degree, trouble is most cities or municipalities are not aware of this law or maybe, just opted that all electrical plans or projects, no matter how small it is, must be signed and sealed by a PEE. REEs were previously called Assistant Electrical Engineers.

It's a pity some Registered Electrical Engineers do not give much importance to taking the PEE board exam. PEEs in my country may even be lesser than 4,500 as of this writing.

There was another EE exam, the Associate Electrical Engineer (AEE), but it was abolished, years back. AEE used to be an option for the Registered EEs to take. Electronics and Communications Engineers who have long experience in the practice of electrical engineering were qualified to take this board exam. Master Electricians who have considerable experience in electrical engineering may be qualified to take this board examination, too. Since AEE exam was abolished, all AEE licensees must have probably been upgraded to REEs.


34.5kV Incomer CT and PT


Light Rail Transit 34.5kV incomer. Supplies redundant 5MVA, 34.5kV/ 605Volts rectifiers and 1- 34.5kV/ 6.6kV auxiliary transformers for power and lighting loads.This 34.5kV incomer is installed in a room not accessible to the building or facility owner. Only personnel of the utility company providing power the system have access to this room

2. The Professional Electrical Engineer (PEE)

The PEE does the same work as that of a REE - with one exception: The PEE is the only one qualified to sign and seal electrical design drawings, calculations, etc. for implementation. He can be the designer himself or a mere Engineer-of-Records or both, which define him as the person who holds all the legal responsibility of assuring the soundness of a project's electrical installations: whether they be big power plants, transmission line, substation, high rise building, or any other electrical projects to which he has reviewed, sealed and signed. PEEs are usually consultants in major electrical portion of any electrical project.

3. The Registered Master Electrician

This is the third classification of a licensed electrical practitioner. A Registered Master Electrician is either a foreman or a supervisor in a construction or electrical installation projects. They are well trained in the installation/erection of various electrical facilities, etc. They gained their expertise mostly from their exposure to actual works upon graduation from a 1 to 2-year electrical or electronic technician course from technical schools. Technical schools' emphasis is hands-on training; they stay clear of theoretical studies and complex electrical design and mathematical manipulations learned in college by engineering students.

Ring Main Units

7.2kV Ring Main Units

34.5kV Ring Main Unit (RMU). Panel 1 is for the 34.5kV incomer, Panel-2 for the 650KVA transformer, and Panel-3 & Panel-4 for rectifier transformers 1 & 2. An RMU is compact switchgear integrating various MV functional units to enable connection, inter-connection, supply and protection of feeders on radial systems

Electrical engineers who are exposed mostly in design works will be impressed on how efficiently an experienced master electrician plan the execution of an electrical installation. They are good, too, on instrumentation and testing and even commissioning works. In case you are assigned to a construction project and have very limited experience in actual electrical installation/erection works, be humble and befriend a master electrician - even if he is your subordinate; he will be very happy to help and provide you with the information you might need in your future projects.