Abstract: A method of installing a projected beam detector can include providing a radiant energy source, providing a reflector, and projecting a radiant energy beam from the source to the reflector. A multi-pixel sensor or camera can be provided. The beam can be reflected from the reflector back to the sensor. A distance between the reflector and the camera can be determined based on a size of an image of the reflector incident on the camera. Where incident intensity corresponds to expected intensity for a predetermined distance, a sensitivity can be set based on the predetermined distance.

Abstract: Systems and methods for optimizing battery life in wireless multi-hop communication systems are provided. Some methods include a child node transmitting a data packet to a parent node in a wireless system, wherein the data packet includes a parent node identifier, data information, and a length of the data information, and wherein the data packet omits inclusion of a child node identifier. Some methods include a parent node receiving a data packet from a child node in a wireless system, wherein the data packet includes a parent node identifier, data information, and a length of the data information, and wherein the data packet omits inclusion of a child node identifier.

Abstract: A method of installing a projected beam detector can include providing a radiant energy source, providing a reflector, and projecting a radiant energy beam from the source to the reflector. A multi-pixel sensor or camera can be provided. The beam can be reflected from the reflector back to the sensor. The distance between the reflector and the camera can be determined based on size of image of the reflector incident on the camera. Where incident intensity corresponds to expected intensity for a predetermined distance, the sensitivity can be set based on predetermined distance.

Abstract: Systems and methods for optimizing battery life in wireless multi-hop communication systems are provided. Some methods include a child node transmitting a data packet to a parent node in a wireless system, wherein the data packet includes a parent node identifier, data information, and a length of the data information, and wherein the data packet omits inclusion of a child node identifier. Some methods include a parent node receiving a data packet from a child node in a wireless system, wherein the data packet includes a parent node identifier, data information, and a length of the data information, and wherein the data packet omits inclusion of a child node identifier.

Abstract: A photo-electric smoke detector includes a source of radiant energy and a closed loop control circuit which responds to a radiant energy feedback signal to adjust an output characteristic of the emitted radiant energy and which evaluates a quality characteristic of the emitted radiant energy. The feedback circuit and the source can be intermittently activated. Emitted radiant energy is directed toward a lens. The feedback signal is proportional to radiant energy reflected or scattered off of the lens.

Abstract: A photo-electric smoke detector includes a source of radiant energy and a closed loop control circuit which responds to a radiant energy feedback signal to adjust an output characteristic of the emitted radiant energy and which evaluates a quality characteristic of the emitted radiant energy. The feedback circuit and the source can be intermittently activated. Emitted radiant energy is directed toward a lens. The feedback signal is proportional to radiant energy reflected or scattered off of the lens.

Abstract: A wireless communications system incorporates a plurality of synchronized wireless units. Each unit minimizes energy requirements by entering a low current, inactive, state between synchronizing signals. The unit automatically enters an active state prior to receipt of the next synchronizing signal.

Abstract: An aspirated smoke detector includes an ambient air flow separation element in combination with a smoke sensing chamber. The flow separation element can be an active or a passive element. Separated ambient, carrying relative small particles can flow into the sensing chamber. Ambient carrying relatively larger particulate matter is excluded from the sensing chamber.

Abstract: An aspirated smoke detector includes an ambient air flow separation element in combination with a smoke sensing chamber. The flow separation element can be an active or a passive element. Separated ambient, carrying relative small particles can flow into the sensing chamber. Ambient carrying relatively larger particulate matter is excluded from the sensing chamber.

Abstract: A wireless communications capability enables field personnel to communicate with a remote control console of a distributed system. A hand held communications unit generates console related messages that are coupled, via local devices, to the remote console.

Abstract: An event detection system has a control element coupled to a plurality of detectors, such as smoke detectors. The control element can be implemented with a programmed processor. The detectors can include a base which removably receives a separable detector housing and electronics. Group boundaries can be specified by incorporating boundary defining electrical elements, such as switches or resistors, into either a respective detector base or into the detector itself. The control element can include instructions for carrying out an automatic addressing process with respect to the detectors. Topology information obtained during the automatic addressing process in combination with the location of the boundary defining elements specifies one or more groups for the control element. In an alternate embodiment, groups can be defined based exclusively on the topology information. In this embodiment, boundary defining electrical elements are not needed.