Abstract: An electric series circuit with plural loads such as light bulbs connected in series and plural solid state switching devices, with each switching device connected in parallel with one of the loads. Each switching device conducts current when the load that it is connected in parallel with does not conduct current because the load is burned out. The solid state switching means may be any device with a breakthrough voltage which is high enough that it does not conduct when all of the loads conduct current normally. When one of the loads is burned out, that load does not conduct current and the entire line voltage appears across the switching means in parallel with the burned out load. The switching means breaks down. Accordingly, the switching means conducts current and current flows to the remaining loads. Accordingly, the remaining light bulbs in a string of light bulbs continue to light. The burned out load may be immediately detected and replaced. The switching means may be a sidac.

Abstract: A lighting fixture composed of a lampholder which can receive an electrical lamp and supply to it AC power and a body member into which the lampholder can be placed for support and protection. A locking member in the form of a flat, resilient metallic band with end portions bent at an acute angle provides a one-way clutch which permits the lampholder to be placed into the body member but prevents its withdrawal. Channels in the interior wall of the body receive the band ends to prevent rotation of the lampholder. The channels are employed in pairs and a single pair or two pairs at right angles to each other are employed.

Abstract: A lampholder mounting system includes a lampholder and a lampholder bracket. The lampholder includes a housing, electrical contacts supported by the housing and electrical conductors interconnected with the housing to the electrical contacts. The housing includes at least one stop-tab slot and at least one bend-tab slot upon an outer surface of the housing. A lampholder bracket includes a mounting plate with a receiving portion for receiving the lampholder. The receiving portion includes at least one upturned bend tab and at least one stop tab for complementing the outer surface of the lampholder housing, wherein the lampholder is snapped into the receiving portion and the at least one bend tab is bent up to lock the lampholder fixedly to the lampholder bracket.

Abstract: A heat flow detector is described which measures a predetermined rate of heat flow in its surroundings, the surroundings being in the proximity of a recessed incandescent fixture which is designed to operate safely in the designated environment. Should the operating environment change for the fixture it will be sensed by the heat flow detector. If the operating environment becomes more dangerous so that a fire or other damage may occur the heat flow sensor will turn the incandescent lamp off and on at a slow rate to indicate the changed operating environment. The heat flow detector will cause a slow turn off and on if an oversize lamp is inserted in the incandescent fixture. The heat flow detector will thus prevent an overloaded condition due to an oversize bulb.

Abstract: A heat flow detector is described which measures a predetermined rate of heat flow in its surroundings, the surroundings being in the proximity of a recessed incandescent fixture which is designed to operate safely in the designated environment. Should the operating environment change for the fixture it will be sensed by the heat flow detector. If the operating environment becomes more dangerous so that a fire or other damage may occur the heat flow sensor will turn the incandescent lamp off and on at a slow rate to indicate the changed operating environment. The heat flow detector will cause a slow turn off and on if an oversize lamp is inserted in the incandescent fixture. The heat flow detector will thus prevent an overloaded condition due to an oversize bulb.

Abstract: A heat flow detector is described which measures a predetermined rate of heat flow in its surroundings, the surroundings being in the proximity of a recessed incandescent fixture which is designed to operate safely in the designated environment. Should the operating environment change for the fixture it will be sensed by the heat flow detector. If the operating environment becomes more dangerous so that a fire or other damage may occur the heat flow sensor will turn the incandescent lamp off and on at a slow rate to indicate the changed operating environment. The heat flow detector will cause a slow turn off and on if an oversize lamp is inserted in the incandescent fixture. The heat flow detector will then prevent an overheated condition due to an incorrect bulb.

Abstract: A heat flow detector is described which measures a predetermined rate of heat flow in its surroundings, the surroundings being in the proximity of a recessed incandescent fixture which is designed to operate safely in the designated environment. Should the operating environment change for the fixture it will be sensed by the heat flow detector. If the operating environment becomes more dangerous so that a fire or other damage may occur the heat flow sensor will turn the incandescent lamp off and on at a slow rate to indicate the changed operating environemnt. The heat flow detector will cause a slow turn off and on if an oversize lamp is inserted in the incandescent fixture. The heat flow detector will thus prevent an overheated condition due to an oversize bulb.

Abstract: A heat flow detector is described which measures a predetermined rate of heat flow in its surroundings. The surroundings being in the proximity of a recessed incandescent fixture which is designed to operate safely in the designated environment. Should the operating environment change for the fixture it will be sensed by the heat flow detector. If the operating environment becomes more dangerous so that a fire or other damage may occur the heat flow sensor will turn the incandescent lamp off and on at a slow rate to indicate the changed operating environment.The heat flow detector will cause a slow turn off and on if an oversize lamp is inserted in the incandescent fixture. The heat flow detector will then prevent an overheated condition due to an incorrect bulb.

Abstract: The present invention teaches a lockable lampholder mounting system wherein a housing containing electrical contacts, such as an electrical wiring device of the type exemplified by an incandescent lampholder or socket, is removably mounted upon a preselected panel by means of a novel clip arrangement. The panel is of the type utilized in a fixture, for example. The clip arrangement includes a resilient clip of predetermined shape formed with at least three bearing surfaces for contacting the panel, and preferably a fourth bearing surface against which a locking tab is biased to prevent rotation and relatively upward movement of the wiring device.