Abstract: A circuit and a method for controlling the dimming of incandescent lights using a pair of antiparallel connected SCRs which are fired at the same frequency as the frequency of the AC line power to achieve phase control of the power supplied to the light. Only one SCR of the pair is utilized in the 0% to 50% brightness range while both SCRs are utilized in the 51% to 100% brightness range.

Abstract: A dimmer rack for mounting a plurality of modular units called dimmer modules is disclosed. Each of the modules is used to provide dimming control for each lighting circuit in a lighting system. The rack is a vertical enclosure and utilizes a plurality of modular shelving elements attached to the sides of each file to define individual receptacles for each module. Tabs in the shelving register with grovoes on the external housing of the dimmer modules, whereby precise tongue and groove mounting of each dimmer module is obtained. The rack provides vertical input power and control signal busses which are mounted side by side at the rear of the rack which register with and are engaged by first mating connectors on the rear of each of the dimmer modules at one end therof.

Abstract: A dimmer module including a dimmer circuit for use in controlling lighting used in theatrical and architectural operations. The module features a low cost, compact, thermally efficient design incorporating circuit breakers, a power device including solid state switches, and toroidal chokes, all components being interconnected using with prefabricated tooled interconnections eliminating conventional wiring in a housing adapted to make all external connections on a plug in basis. The housing structure incorporates a built-in handle and a plurality of parallel air flow paths to maximize cooling efficiency.

Abstract: A self-contained portable unit for use with theater and television dimming systems and, in particular, with one control console of a microprocessor-based lighting control system having a data display device such as a CRT. The unit includes a digitizer tablet, a stylus and an overlay to be placed on the tablet. The keyboard of the console is reproduced in the overlay in the form of keys replicating indicia printed or silk-screened on the overlay. An area is also provided on the overlay for placement of the designer's lighting pattern layout. Lighting pattern information and lighting levels are entered into the system by the unit by touching the stylus to specific points in the layout and to specific key indicia selected by the user. Initially, each symbol on the lighting pattern layout is defined by using the unit or the console to enter the channel, the light level in each channel, cueing instructions, or other information which the symbol represents into the system.