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 M.
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 in squads or groups of two
or three students and the work 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


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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 cannot prove to be other than beneficial in the
later work when the engineer must rely upon his own ingenuity to
a great extent.