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This programme is in two parts. In the first part Mr. Brian Bowers of the Science Museum considers some of the important stages in the development of electric generators from Faraday's disc to the ...practical machines which provided public and domestic lighting in the 1880's. Speaking from the electrical power gallery of the Science Museum, he illustrates these stages with reference to machines from the museum's collection. In the second part of the programme Mr. B. J. Prigmore of the Imperial College of Science and Technology, London, considers some stages in the development of electrical traction. The early development considered in this programme is confined to traction equipment powered by direct current. Such traction equipment consists of three essential parts: 1. The armature which revolves in a magnetic field driving the vehicle's wheels; 2. The field electro-magnets which linked electrically in series with the armature windings provide the magnetic field; 3. The control equipment which enables electric motors to be used to produce the various vehicle speeds required. To demonstrate their development, Mr. Prigmore shows electric traction equipment built between 1895 and 1905 and still in use on the Manx Electric Railway.
Metadata describing this Open University video programme
Module code and title: AST281, Science and the rise of technology since 1800
Item code: AST281; 10
First transmission date: 12-09-1973
Published: 1973
Rights Statement:
Restrictions on use:
Duration: 00:24:15
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Producer: Nat Taylor
Contributors: Brian Bowers; B J Prigmore
Publisher: BBC Open University
Keyword(s): Electricity generating machines; Manx Electric Railway; Michael Faraday; Tramways
Footage description: Brian Bowers introduces the programme. He reproduces Faraday's experiment in which a wire is moved through the lines of force of a magnet introducing an electric force in the wire. Brian Bowers demonstrates and describes the machine for generating electric power designed by Hippolyte Pixii. Continuing his description of electricity generating machines up to ca. 1870, Bowers demonstrates the Saxton machine. Bowers describes a generator made by E. M. Clarke, and goes on to show and describe the generator made for use in electro plating one of the first applications of generated electricity. Bowers then describes the use of generated electric power in lighthouses, the second main application. He shows and describes a generator designed by F. H. Holmes and used in a lighthouse being installed in 1871. Having touched upon the limitations of the machine so far described, Bower goes on to describe the subsequent technical developments that overcame these limitations; double arrangement and self excitation. Wheatstone's and Werner Siemens' self excited generator: are shown. Bowers now describes the invention of Pacinotti, i.e. ring winding, reinvented by Z.T. Gramme. He describes the first electric street lighting schemes. Over shots of the Manx Electric Railway tram cars, B. J. Prigmore begins his description of the development of the electric motor. Prigmore examines both a ringwound armature and drum armature, detailing the disadvantages of the former. Examples of these armatures from motors of the Manx Electric Railway are shown at the beginning of the sequence. Prigmore moves on to the slotted armature. Again an example is shown and described. Prigmore now passes on to the developments that took place in the magnetic field for the motor. Examples are shown progressing from the horseshoe magnet of a motor of a 1895. Prigmore describes a four pole machine. Prigmore goes on to describe the methods of control, explaining the difficulties and showing a face plate controller. Prigmore describes the disadvantages of the face plate controller for traction motors and describes and demonstrates the drum controller. The method of overcoming dangerous sparking when breaking the final contacts is also described. Prigmore ends the programme with a description of the benefits of electric tramways over shots of the Manx Electric Railway.
Master spool number: 6HT/71185
Production number: 00525_3038
Videofinder number: 3370
Available to public: no