The present invention provides a Control Module 15 for controlling a dual filament bulb, in particular aircraft reading lamps, so as to detect the failure of one filament and energize the other filament. The Control Module 15 also has provisions for detection of bulbs that have only one or no operable filament(s) by activating an indicator (Light Emitting Diode) or connection to a test switch that will command the Module to activate bulbs that have two operable filaments only. The Control Module 15 consists of a solid state circuit made up of triacs, resistors, capacitor, diodes and fuse all packaged in a small printed circuit board. Interface between the Module and dual filament bulb, indicator or test switch is easily accomplished by a small connector on the Control Module 15.
An LED lamp device is made up of an LED emitter, a pair of DC voltage input terminals, a circuit connecting between the LED emitter and the pair of DC voltage input terminals, and at least one constant-voltage diode and at least one constant-current diode which are interposed in the circuit. The LED lamp device further has an adapter for mounting on one end thereof the LED emitter, and a base fixed to the other end of the adapter. The lighting parts such as the constant-voltage diode or the like are contained inside the adapter and the base.
False ac signals produced by a noise suppression capacitor across a switch applying a switched ac line voltage signal to a logic input of a microprocessor in an electrical apparatus such as, for example, a contactor or circuit breaker, are phase shifted with respect to a true ac input by inserting two series resistors, and a diode shunting one resistor, between the switch and the logic input. This creates a larger window in which to discriminate between the zero crossings of the true and false ac signals.
An improved ion source is provided with multiple filaments and wiring for selectively connecting various combinations of filaments to a current source. In one embodiment an additional filament is a spare filament which is connected to the current source when the primary filament burns out. This decreases down time due to filament replacement. In another embodiment, an additional filament operates simultaneously with a primary filament to provide a more homogenous electron cloud and to increase filament life.
A light emitting device includes at least a first light source which is connectable to an energy source, a second light source, detector means for detecting a failure of the first light source, and switch means, responsive to the detector means, for enabling the connection of the second light source to the energy source when the detector means detects failure of the first light source.
A power supply system has a battery for supplying power and a lamp having a plurality of filaments therein. Each of the filaments is connected to the battery through a filament power feed line, respectively. A switch is provided on each of the filament power feed line. A fault detection circuit measures a current that flows in a non-active filament and generates a fault signal that shuts off the switch for the filament when the current flows in the non-active filament.
