University of Virginia Library

LABORATORY WORK IN ELECTRICAL ENGINEERING.

The Scott Laboratory of Electrical Engineering.—This laboratory
was initially equipped and endowed by Mrs. Frances Branch Scott, of
Richmond, Va., as a memorial to her late son, an alumnus of this university.
During the year 1910 the equipment was substantially increased
through the generosity of the Hon. Charles R. Crane, of Chicago, Ill., a
friend of the university. During 1912, still further substantial additions
were made, consisting of measuring instruments, auxiliary control apparatus,
and more particularly a steam-turbine driven alternating current,
three-phase, generator with exciter and control switchboard.

In addition to full sets of electric meters with the appliances for
testing and calibrating them, galvanometers of the best modern types,
standard cells and resistances, standard condensers, and other pieces of
apparatus for minor tests, it contains numerous pieces of the very best
construction. Such are the Wolff Potentiometer, the Siemens and Halske
Thomson Double Bridge, the Koepsel Permeameter, the Duddell Double
Projection Oscillograph, the Station Photometer with Lummer-Brodhun
screen, the Carey-Foster Bridge and others. For the work in machine
testing there are a number of direct current generators and motors, series,
shunt and compound, an interpole motor, a double current generator, a
two-phase alternator, a General Electric experimental test set for alternating
current, comprising a generator furnishing single, two, three, six
or twelve-phase current, and, in addition, offering three types of induction
motors with all necessary starting and controlling devices, a single-phase
repulsion motor, a two-phase induction motor, two three-phase induction
motors, several pairs of constant voltage transformers, a constant current
transformer, frequency meters, power factor indicator, synchronism indicator,
ground detector and the auxiliary apparatus used in testing these
machines. The laboratory has been arranged with a system of universal
plug and receptacle connections to facilitate the setting up of all experimental
combinations.

The laboratory work is carried on by the students in squads or groups
of two or three and is so arranged that each student will become familiar
with all the details and connections of each particular test. A most
important feature of the laboratory instruction is the required preparation
of a preliminary report on each experiment before the actual test
is carried out. These preliminary reports are written up in the classroom
at assigned hours and consist of a complete résumé of the test under
discussion. The object, the theory, the scheme of connections necessary,
the choice of measuring instruments and all auxiliary devices needful for
the proper performance of the experiment are here worked out and this
preliminary report is handed in for correction or approval. After approval,
the test is assigned for a definite laboratory hour and the work is then
carried through. A final report is then handed in consisting of the preliminary
and the additional data in tabulated and in graphical form. Such
a final report comprises a complete text on any given experiment and will
prove of great value in later work in commercial fields. It is recognized
that the outlined method for laboratory work is of the greatest benefit to
the student inasmuch as it requires a thorough understanding of each given
test, and at the same time inculcates habits of self-reliance and a spirit
of originality which can not prove to be other than beneficial in the later
work when the engineer must rely to a great extent upon his own ingenuity.