Publication: Western Electrician
Chicago, IL, United States
A New Design of Pole-Top.
Refinement in the construction of the overhead equipment of the electric road is now the order of the day. It is only lately, however, that engineers have turned their attention to the features needed in pole-tops. As is well known, these should be strongly made, so shaped as to shed the water, and should insulate both trolley
and guard wires from each other and from the pole. There should be also provided ready means for taking up the slack in both suspension wires and feeder insulators. These features all seem to be found in the new pole-top designed by Edmund Verstraete, the electrician in charge of the construction of the Union Depot Railway company's plant in St. Louis.
As the cut shows, this cap is of iron, and is so designed that it may be used with either iron or wooden poles. The wooden poles do not need to fit it tightly, as the pull of the guy wires will keep it pressed against one side of the pole. The pole-top is merely slipped over the end of the poles, the top adjusting itself. With iron poles a wooden plug and bushing are used, as shown in the section. These bushings are thoroughly soaked with Simplex paint, and as the iron flange keeps the adjacent part of the pole dry, the casting is always insulated from it. The lower end of the pole-top is flared out so as to shed the water. This construction insures the insulation of the trolley wire from the ground. The suspension wires are wound on a drum, whose enlarged ends are provided with six holes. A pin through one of these holes keeps the drum from unwinding. These pins allow the slack of the wires to be readily taken up. The drum for the guard wires is 9 inches above that for the trolley wire. These drums are made of insulating material. The insulators for carrying the mains or feeders are set above the guard wire. By this arrangement, if both the trolley and the guard lines are put up before the mains are strung, the latter need not be slipped through between the suspension wires, but may be readily thrown over the top and fastened to the insulators. This feature will be appreciated. The Great Western Electric Supply company, Chicago, is handling the device.
|Date completed:||January 6, 2009 by: Bob Stahr;|