Abstract :
R. R. Cowles: The present tendency of the Pacific Gas & Electric Company is toward the use of small series street-lighting loops with incandescent lamps only. These series loops are 6.6-ampere and are supplied from a multiple-series constantcurrent transformer installed on the pole in the same manner as any other distribution transformer. These constant-current transformers are of the moving-coil type, fundamentally similar to those formerly used inside of stations. In size they range from 5 to 20 kw. each, depending upon the average size of the series incandescent lamps which are connected to the circuit. It is the aim to avoid long loops and to restrict the number of lamps per circuit to approximately 60.