Exhibitors Herald and Moving Picture World (Apr-Jun 1930)

94 Better Theatres Section April 12, 1930 I vfKj s ifl Hr ■ K,' j ! §p The Bifocal f 2.5 Super-Lite Lens THIS new convertible Projection Lens is now in use in a great many of the Leading Theatres of the country due to the fact that it meets all the requirements presented with the use of both Sound and Silent Film, without changing the Projection Lens in the machine. The manner in which the sound picture is shifted and centered on the screen is just another quality of this wonderful product. _ PROJECTION OPTICS CO., INC. 330 Lyell Ave. ROCHESTER, N. Y., U. S. A. -Rialto Import Corporation, 135 W. 44th Street, New York City. Shapiro & Arnson, 20 Warren Street, New York City. The Voigt Company, 1743 N. 12th Street, Philadelphia, Pa. Lighting, Flood Refer to FLOOD LIGHTING A Lighting, Stage, Equipment Refer to STAGE LIGHTING EQUIPMENT A Lighting and Power Plants EMERGENCY lighting plants are ^ equipment designed to furnish power for supplying illumination and operating the show in the event of a failure of the local power supply. It is said that the financial loss suffered by admissions returned by a theatre through only one power failure a year would more than compensate for the cost of equipment of this type. In addition to financial loss, a power failure during a performance frequently results in loss of life and property through the resultant panic. Emergency lighting plants are made in several types such as the gasoline engine type, water turbine type, motor generator and battery type. In the case of the motor generator type several •sources of power are provided to meet every contingency, which, together, form an interlocking type of protection. The first source of power for the emergency lights of the theatre is the regular power supply, either from central station lines or from private generating plant. In the case of the private electric plant, if it is automatically oper ated, it can be so installed with an automatic transfer switch that the instant the regular supply of current fails, the private electric plant is automatically started. The electric plant then supplies the electrical needs of the theatre to the extent of its capacity. This it continues to do for as long as the regular supply is shut off. When this service is again resumed, the plant automatically stops. The second source for the emergency, exit or hazard line circuits, is a special heavy duty glass jar storage battery, which is automatically kept charged by a motor generator set or rectifier. The capacity of the plant depends upon the total necessary load and the length of time protection is desired. The normal alternating current is fed through the transfer switch direct to the lighting lines and in the event of power failure, the batteries to the lighting lines. The batteries then supply the necessary power until the normal service is resumed, or until the batteries are discharged. In some states the emergency, exit and hazard light circuits must be of a lower voltage than that of the normal power supply lines. In such cases, a transformer is used to step-down the supply line voltage to that of the emergency circuit voltage. The third source of supply for the emergency circuits is the motor generator set itself. In case the A. C. transformer circuit, which normally feeds the 32-volt lights, should fail the motor gen erator set is operated from the main power supply line and connected to the emergency exit light circuits through the battery circuit. The battery will carry the lights only as long as necessary to start the motor generator set. After the motor generator is started the battery floats on the line. The heavy-duty storage battery is kept continuously charged by means of a motor generator set, which is operated from the regular power lines, on an individual circuit separate from the mergency circuits. Enslen Hydro & Electric Co., Inc., 1600 Broadway, New York City. Fairbanks, Morse & Company, Beloit, Wis. Kohler Company, Kohler, Wis. ROTH BROTHERS, 1400 W. Adams Street, Chicago, 111. Universal Motor Company, Oshkosh, Wis. Weir-Kilby Corporation, Station H, Cincinnati, O. WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, East Pittsburgh, Pa. Lights, Aisle Refer to AISLE LIGHTS Lights, Exit Refer to EXIT LIGHT SIGNS Lights, Snot AR.E made in arc and incandescent types for use on stage — in the booth — in cove lighting, and for head spotting. Most spotlights on the market can be used for spot lighting and for full flood. The arc types are made in sizes of 3 ampere up to 150 ampere. They come complete with stand and attachment cord and connecter. Within the last year, the high intensity spot has appeared. It is an adaptation of the high intensity lamp to spot and flood-lighting. The incandescent spotlights are in sizes of from 250 watt to 2,000 watt. The sizes usually used are 250, 400, 500 and 1,000 watt. The small head spots of 250 watts are used for cove lighting or spotting the head of a singer or organist. The incandescent spotlights come either with floor standard or pipe hangers for border lighting batons. In stage work spotlights are frequently banked one above the other on a stand and used for floodlighting from the wings. Prices range from $12 to $500. FRANK ADAM ELECTRIC COMPANY, 3650 Windsor Avenue, St. Louis, Mo. BELSON MANUFACTURING COMPANY, 800 Sibley Street, Chicago, 111. BEST DEVICES COMPANY, Filin Building, Cleveland, O. Brenkert Light Projector Company, 7348 St. Aubin Avenue, Detroit, Mich. CHICAGO CINEMA EQUIPMENT COMPANY, 17361754 N. Springfield Avenue, Chicago, 111. HALL & CONNOLLY, INC., 24 Van Dam Street, New York City. HUB ELECTRIC COMPANY, 2225 W. Grand Avenue, Chicago, 111. KLIEGL BROTHERS, 321 W. 50th St., New York City. Major Equipment Company, 4063 Fullerton Avenue, Chicago, 111. Milwauke Electric Switchboard Company, 156 Clinton Street, Milwaukee, Wis. W. G. Preddey, 188 Golden Gate Avenue, San Francisco, Cal. Reflector & Illuminating Company, 1417 W. Jackson Boulevard, Chicago, 111. Twin City Scenic Company, 2819 Nicollett Avenue, Minneapolis, Minn. Westinghouse Lamp Company, 150 Broadway, New York City. Wm. Wurdaek Electric Manufacturing Company, 4444 Clayton Avenue, St. Louis, Mo. Liquid Soap Refer to SANITARY SPECIALTIES