Abstract: A life safety device includes a battery assembly with a rechargeable battery. Extended shelf life is achieved by annually initiating an over-discharge protection mode in which a battery protection circuit prevents current flow from the battery. The life safety device remains in the over-discharge protection mode until the device is connected to a charging power source at the time of installation. The battery assembly then exits the protection mode and enters its normal mode of operation.

Abstract: When a rechargeable battery of a life safety device reaches its end of life, the life safety device provides an audible signal indicating that replacement is required. When the device is disconnected from line power, the rechargeable battery still contains a significant amount of energy. The device automatically begins controlled discharge the battery until the stored energy has been reduced to a safe level for disposal of the life safety device and its battery.

Abstract: When a rechargeable battery of a life safety device reaches its end of life, the life safety device provides an audible signal indicating that replacement is required. When the device is disconnected from line power, the rechargeable battery still contains a significant amount of energy. The device automatically begins controlled discharge the battery until the stored energy has been reduced to a safe level for disposal of the life safety device and its battery.

Abstract: A life safety device includes a battery assembly with a rechargeable battery. Extended shelf life is achieved by annually initiating an over-discharge protection mode in which a battery protection circuit prevents current flow from the battery. The life safety device remains in the over-discharge protection mode until the device is connected to a charging power source at the time of installation. The battery assembly then exits the protection mode and enters its normal mode of operation.

Abstract: A life safety device can include a battery monitoring module configured to measure a voltage level of a battery, an alarm module configured to provide an alarm when the voltage level is less than or equal to a low battery threshold, and a silence module configured to silence the alarm for a random time period.

Abstract: A life safety device can include a sensor configured to sense a hazardous condition, an interconnect module configured to communicate the hazardous condition to a wired life safety device using one or more wires, and a transceiver module configured to wirelessly communicate the hazardous condition to a wireless life safety device.

Abstract: A method of radio frequency communication for a life safety device including a controller, a hazardous condition sensor, an alarm device, and a radio frequency communications device including transmitting and receiving capability. One method includes receiving a test signal using the radio frequency communications device, lowering a voltage to the hazardous condition sensor to simulate a hazardous condition to test the hazardous condition sensor, and emitting an alarm using the alarm device if the hazardous condition sensor passes the test. Another method includes before transmitting a radio frequency signal, turning on the radio frequency communications device for a period of time, and delaying transmission if the radio frequency communications device receives a header, deadtime and startbit. Yet another method includes sending a test signal at a first transmission power level, and sending an alarm signal at a second transmission power level greater than the first transmission power level.

Abstract: A detector assembly is adapted to be removably secured to a female electrical receptacle connected to a power supply where the female receptacle is mounted at a surface of a structure. The detector apparatus includes a housing and an electrically powered circuit mounted in the housing. The circuit includes components operable to detect an alarm condition (such as carbon monoxide or smoke) and to provide an alarm in response to the detection. A primary power source includes a male electrical connector secured to the housing and extending outwardly there from. A secondary power source includes a battery connector mounted within the housing and adapted to removably receive a battery contained within the housing. The circuit is adapted to draw power from the secondary source in the event of a detected loss of power from the primary source. The apparatus includes a sensor for sensing displacement of the housing from the female electrical receptacle.

Abstract: A detector assembly is adapted to be removably secured to a female electrical receptacle connected to a power supply where the female receptacle is mounted at a surface of a structure. The detector apparatus includes a housing and an electrically powered circuit mounted in the housing. The circuit includes components operable to detect an alarm condition (such as carbon monoxide or smoke) and to provide an alarm in response to the detection. A primary power source includes a male electrical connector secured to the housing and extending outwardly there from. A secondary power source includes a battery connector mounted within the housing and adapted to removably receive a battery contained within the housing. The circuit is adapted to draw power from the secondary source in the event of a detected loss of power from the primary source. The apparatus includes a sensor for sensing displacement of the housing from the female electrical receptacle.

Abstract: A life safety device can include a sensor configured to sense a hazardous condition, an interconnect module configured to communicate the hazardous condition to a wired life safety device using one or more wires, and a transceiver module configured to wirelessly communicate the hazardous condition to a wireless life safety device.

Abstract: A life safety device can include a battery monitoring module configured to measure a voltage level of a battery, an alarm module configured to provide an alarm when the voltage level is less than or equal to a low battery threshold, and a silence module configured to silence the alarm for a random time period.

Abstract: A method of radio frequency communication for a life safety device including a controller, a hazardous condition sensor, an alarm device, and a radio frequency communications device including transmitting and receiving capability. One method includes receiving a test signal using the radio frequency communications device, lowering a voltage to the hazardous condition sensor to simulate a hazardous condition to test the hazardous condition sensor, and emitting an alarm using the alarm device if the hazardous condition sensor passes the test. Another method includes before transmitting a radio frequency signal, turning on the radio frequency communications device for a period of time, and delaying transmission if the radio frequency communications device receives a header, deadtime and startbit. Yet another method includes sending a test signal at a first transmission power level, and sending an alarm signal at a second transmission power level greater than the first transmission power level.