Tuesday, March 10, 2015

High Voltage switches and its purpose

3-Phase Protection And Interruption
Circuit switches were developed for fusing and substation power transformers and to overcome its drawbacks. SF6 Gas interrupters in the circuit switchers are designed to

provide 3-Phase Interruption and protection for transient over loads and over voltages at a better better price comparatively.

Also it can provide protection from power transformers bugs due to differential, sudden pressure, and over current relay schemas as well as critical operating constraints like low oil level, hight oil, temperature variations due to winding and pressure relief device operations.

New models were designed with advanced interrupters that will reduce the amount of gaps needed for good performance to a 1 Gap per phase, because it needs to eliminate the

necessity of the disconnect switch blades in series with interrupter.

Tuesday, February 24, 2015

Steinmetz on Electrical Engineering Education in 1908

If it feels like people have been sounding off on electrical engineering education for years, then perhaps here’s some evidence from over a century ago to confirm this. Charles P. Steinmetz, one of the giants of the field, wrote a scathing critique of engineering education in a 1908 paper titled “Electrical Engineering Education”..

 

Below are some of the choice snippets from the paper (in no particular order), some of which are as relevant now as they were over a hundred years ago:
“When the student enters college he is not receptive to an intelligent understanding, for after a four years’ dose in the high school of the same vicious method of memorizing a large mass of half and even less understood matters, the student finds it far easier to memorize the contents of his textbooks than to use his intelligence to understand the subject matter. After graduation, years of practice do for the better class of students what the college should have done-teach them to understand things.”
“Fortunately, the better technical colleges realize that the first requirement of an electrical engineer is a thorough general education, and begin to realize that for this purpose it is not sufficient; to require general subjects for college entrance and relegate their study to the high school: for even if the average high school were what it should be and not what it actually is, much of the general knowledge required by an educated man cannot be taught in the high school, since during the high-school years the intelligence of the boy is not sufficiently ripened for its grasp, and a review in the college is necessary.”
“The glaring fault of the college curriculum is that quantity and not quality seems to be the object sought: the amount of instruction crowded into a four years’ course is far beyond that which even the better kind of student can possibly digest. Memorizing details largely takes the place of understanding principles, with the result that a year after graduation much of the matter which had been taught has passed out of the memory of the student, and even examinations given to the senior class on subjects taught during the freshman and sophomore years, reveal conditions which are startling and rather condemnatory to the present methods of teaching.”
“The great defect of the engineering college is the insufficient remuneration of the teaching staff: the salaries paid are far below those which the same class of men command in industrial work, and as a result the college cannot compete with the industry for its men, but most of the very best men are out of reach for the colleges.”