Operation of Projection Arcs from Motor Generator Sets

C. C. Dash

When series are generators were introduced and used successfully in theaters, the projection requirements were relatively simple. The projection room equipment usually consisted of two projectors with vertical carbon lamps with the addition in some instances of a spot lamp requiring the same amount of current as the projectors. Arc controls first introduced and used were mostly of the intermittent type using a voltage relay, the coil of which is connected across the arc, in connection with an operating motor. The operation of these lamps was successful with the series arc generators, and as no ballast resistance was used in the projection arc circuit a maximum converting efficiency from alternating current supply to direct current for the lamps was obtained.

Print ISSN
Published
1930-11
Content type
Original Research
DOI
10.5594/J05613