The paper shows how ripple signals superimposed upon power system voltages can be used for load switching. It mentions early ripple schemes used for street lighting control and refers specifically to two rhythmatic schemes installed in london. It goes on to compare early installations with modern schemes made possible by the advent of solid state electronic equipment and indicates the economic and technical differences between the old and the new. In anticipating a revival in centralised switching systems the paper suggests that electricity boards could, in the future, provide flexible switching facilities to local authorities for public lighting. It concludes by stressing the importance in any future installations of co-operation between designers, operators and users. (Author/publisher)
Abstract