Abstract: A method for reducing the barriers between creative designs and complete drawings and databases by generating complex engineering drawings, such as lighting systems from lines and/or other simple shapes automatically, eliminates the tedious, time-consuming tasks of drawing, placing and annotating elements of structure, such as mounting trusses, fixtures, lighting patterns (often referred to as “gobos”), projectors and any other lighting, sound, video, plumbing, HVAC, street layouts or other graphical representations.

Abstract: An improved method and apparatus for handling the large load currents which occur with overloads, short circuits, and momentary overcurrents such as in starting motors or cold incandescent lamp filaments. The method involves turning the load current off when an overcurrent is detected, and then back on again before the end of the half-cycle in which the overcurrent occurred. This allows more current to flow during the half-cycle without the need to increase the peak current capability of the power-handling components. With an incandescent lamp load, this results in more rapid lamp brightening without the need for larger, more expensive components. Several embodiments are disclosed which respond to different features of the power line voltage cycle, including a very low-cost microprocessor circuit and power supply.

Abstract: An improved phase-controlled power control apparatus includes a semiconductor switching element for varying the effective power delivered to a load from the power lines. The conduction angle of the semiconductor power switch element is varied from a nominal angle to compensate for changes in power line voltage and for changes in load current. The amount of load current flow is continuously compared to the power line voltage to detect any overcurrent condition, even very close to the zero-crossing of the power line voltage. The shape of the transition from load current on to load current off (or vice versa) in controlled to minimize audible noise from the load. The load current can be shared between a plurality of compatible power control sections.

Abstract: A lighting control circuit is provided for controlling illumination and dimming of at least one light in a lighting circuit for operation at a selectable one of a plurality of applied voltages. The lighting control circuit includes a power supply circuit for receiving an AC line voltage input and for converting the AC line voltage to selectable rectified AC and DC power for delivery to the lighting control circuit. A timing generator circuit is also coupled with the power supply circuit and is responsive to a rectified AC sample from the power supply for generating and shaping an electrical timing signal. A timing comparator circuit is responsive to the electrical timing signal for generating a variable duty cycle output signal. A switching control circuit is coupled with the lighting circuit for gating current therethrough in accordance with the variable duty cycle output control signal.