Abstract: A monitoring system for monitoring operation of a refrigerant-cycle system is disclosed. A first temperature sensor measures a first temperature of air at a first location downstream of an evaporator. A second temperature sensor measures a second temperature of air a second location upstream of the evaporator. A processing system determines a temperature drop across the evaporator based on the first temperature, the second temperature, and a humidity of air. The processing system that determines whether airflow through the evaporator is restricted based on the temperature drop across the evaporator.

Abstract: A monitoring system for monitoring operation of a refrigerant-cycle system is disclosed. A plurality of sensors measure operating characteristics of the refrigerant-cycle system. The refrigerant-cycle system includes a condenser unit and an evaporator unit. The condenser unit includes a condenser and a compressor. The evaporator unit includes an evaporator and a fan. A processing system receives the measurements from the plurality of sensors and outputs data regarding operation of the refrigerant-cycle system to a remote monitoring system.

Abstract: A monitoring system for monitoring operation of a refrigerant-cycle system is disclosed. A differential pressure sensor measures a pressure difference between: (i) air at a first location upstream of an evaporator of the refrigerant-cycle system; and (ii) air at a second location downstream of the evaporator of the refrigerant-cycle system. An electrical sensor measures an electrical quantity indicative of power consumption of the refrigerant-cycle system. A processing system determines whether airflow through the evaporator is restricted based on the pressure difference. The processing system calculates an efficiency of the refrigerant-cycle system based on the power consumption of the refrigerant-cycle system.

Abstract: A sensor unit that includes at least one sensor configured to measure an ambient condition is described. The controller can be configured to receive instructions, to report a notice level when the controller determines that data measured by the at least one sensor fails a report threshold test corresponding to a report threshold value. The controller can also be configured to obtain a plurality of calibration measurements from the at least one sensor during a calibration period and to adjust the threshold based on the calibration measurements. The controller can be configured to compute a first threshold level corresponding to background noise and a second threshold level corresponding to sensor noise, and to compute the report threshold value from the second threshold. In one embodiment, the sensor unit adjusts one or more of the thresholds based on ambient temperature.

Abstract: Various devices, systems, and methods may be presented. A wireless device may include a smoke sensor configured to obtain measurement data regarding a level of smoke. The wireless device may operate in a sleep mode while the smoke sensor obtains the measurement data. The wireless device may determine, from the measurement data, whether the level of smoke has exceeded a warning threshold. In response to determining that the level of smoke has exceeded the warning threshold, the wireless device may communicate a warning indication. The wireless device may determine, from the measurement data, whether the level of smoke has exceeded an alarm threshold. In response to determining that the level of smoke has exceeded the alarm threshold, the wireless device may communicate an alarm indication, the alarm indication indicating that the alarm threshold has been exceeded.

Abstract: Various devices, systems, and methods may be presented. A sensor unit may be presented that includes a housing and a chamber arranged within the housing. The sensor unit may include a controller arranged within the housing. The controller may receive information from an HVAC (heating ventilation and air conditioning) system, wherein the information is indicative of operation of the HVAC system. The controller may determine an effect of the HVAC system on measurements made by the sensor using the information from the HVAC system.

Abstract: Various embodiments of wireless ambient sensor unit are presented. The sensor unit may include a wireless transceiver configured to transmit sensor data and to receive instructions. The sensor unit may include a sensor configured to measure an ambient condition. The sensor unit may include a controller in communication with the wireless transceiver and the sensor. The controller may be configured to compare data measured about the ambient condition to a stored threshold while the wireless ambient sensor unit is functioning in a low-power mode. The controller may be configured to exit the low-power mode in response to the comparison of the data with the stored threshold. The controller may be configured to cause the data measured about the ambient condition to be transmitted by the wireless transceiver as one or more messages in response to the comparison to the stored threshold.

Abstract: A monitoring system for monitoring operation of a refrigerant-cycle system is disclosed. An electrical sensor measures an electrical quantity indicative of power consumption of a component of the refrigerant-cycle system. A processing system selectively identifies a condition indicative of an airflow restriction through the refrigerant-cycle system based on the power consumption of the component.

Abstract: Arrangements for measuring environmental conditions using a wireless sensor system may be presented. A threshold value may be determined for a sensor unit arranged in the wireless sensor system. The threshold value may be programmed in to the sensor unit. Quantitative sensor data may be measured about an ambient environmental condition. The measured quantitative sensor data may be compared to the programmed threshold value. The measured quantitative sensor data may be determined to exceed the programmed threshold value. Information indicative of the measured quantitative sensor data may be transmitted in response to determining that the measured quantitative sensor data exceeds the programmed threshold value.

Abstract: Various devices, systems, and methods may be presented. A sensor unit may be presented that includes a housing and a chamber arranged within the housing and configured to receive air from outside of the housing of the sensor unit. Also present may be a sensor arranged within the housing and configured to measure a characteristic within the chamber. The sensor unit may include a fan arranged within the housing in relation to the chamber, the fan configured to clear air from the chamber of the sensor unit. Further, the sensor unit may include a controller in communication with the fan and the sensor, the controller configured to operate the fan.

Abstract: Various devices, systems, and methods may be presented. A sensor unit may be presented that includes a housing and a chamber arranged within the housing. The sensor unit may include a controller arranged within the housing. The controller may receive information from an HVAC (heating ventilation and air conditioning) system, wherein the information is indicative of operation of the HVAC system. The controller may determine an effect of the HVAC system on measurements made by the sensor using the information from the HVAC system.

Abstract: An arrangement for measuring environmental conditions in a wireless sensor system. A threshold value may be determined. An environmental condition sensor unit may measure, over a defined period of time, an environmental condition level. The measured environmental condition level may be compared to the determined threshold value. It may be determined whether the measured environmental condition level exceeds the defined threshold value for the defined period of time. At least in part based on the determination of whether the measured environmental condition level exceeds the defined threshold value over the defined period of time, information indicative of the measured environmental condition level may be transmitted.

Abstract: Various devices, systems, and methods may be presented. A wireless device may include a smoke sensor configured to obtain measurement data regarding a level of smoke. The wireless device may operate in a sleep mode while the smoke sensor obtains the measurement data. The wireless device may determine, from the measurement data, whether the level of smoke has exceeded a warning threshold. In response to determining that the level of smoke has exceeded the warning threshold, the wireless device may communicate a warning indication. The wireless device may determine, from the measurement data, whether the level of smoke has exceeded an alarm threshold. In response to determining that the level of smoke has exceeded the alarm threshold, the wireless device may communicate an alarm indication, the alarm indication indicating that the alarm threshold has been exceeded.

Abstract: A sensor unit that includes at least one sensor configured to measure an ambient condition is described. The controller can be configured to receive instructions, to report a notice level when the controller determines that data measured by the at least one sensor fails a report threshold test corresponding to a report threshold value. The controller can also be configured to obtain a plurality of calibration measurements from the at least one sensor during a calibration period and to adjust the threshold based on the calibration measurements. The controller can be configured to compute a first threshold level corresponding to background noise and a second threshold level corresponding to sensor noise, and to compute the report threshold value from the second threshold. In one embodiment, the sensor unit adjusts one or more of the thresholds based on ambient temperature.

Abstract: A sensor unit that includes at least one sensor configured to measure an ambient condition is described. The controller can be configured to receive instructions, to report a notice level when the controller determines that data measured by the at least one sensor fails a report threshold test corresponding to a report threshold value. The controller can also be configured to obtain a plurality of calibration measurements from the at least one sensor during a calibration period and to adjust the threshold based on the calibration measurements. The controller can be configured to compute a first threshold level corresponding to background noise and a second threshold level corresponding to sensor noise, and to compute the report threshold value from the second threshold. In one embodiment, the sensor unit adjusts one or more of the thresholds based on ambient temperature.

Abstract: A sensor unit that includes at least one sensor configured to measure an ambient condition is described. The controller can be configured to receive instructions, to report a notice level when the controller determines that data measured by the at least one sensor fails a report threshold test corresponding to a report threshold value. The controller can also be configured to obtain a plurality of calibration measurements from the at least one sensor during a calibration period and to adjust the threshold based on the calibration measurements. The controller can be configured to compute a first threshold level corresponding to background noise and a second threshold level corresponding to sensor noise, and to compute the report threshold value from the second threshold. In one embodiment, the sensor unit adjusts one or more of the thresholds based on ambient temperature.

Abstract: A sensor unit that includes at least one sensor configured to measure an ambient condition is described. The controller can be configured to receive instructions, to report a notice level when the controller determines that data measured by the at least one sensor fails a report threshold test corresponding to a report threshold value. The controller can also be configured to obtain a plurality of calibration measurements from the at least one sensor during a calibration period and to adjust the threshold based on the calibration measurements. The controller can be configured to compute a first threshold level corresponding to background noise and a second threshold level corresponding to sensor noise, and to compute the report threshold value from the second threshold. In one embodiment, the sensor unit adjusts one or more of the thresholds based on ambient temperature.

Abstract: A low cost, robust, wireless sensor that provides an extended period of operability without maintenance is described. The wireless sensors are configured to communicate with a base unit or repeater. When the sensor unit detects an anomalous ambient condition (e.g., smoke, fire, water, etc.) the sensor communicates with the base unit and provides data regarding the anomalous condition. The sensor unit receives instructions to change operating parameters and/or control external devices.

Abstract: A low cost, robust, wireless sensor that provides an extended period of operability without maintenance is described. The wireless sensors are configured to communicate with a base unit or repeater. When the sensor unit detects an anomalous ambient condition (e.g., smoke, fire, water, etc.) the sensor communicates with the base unit and provides data regarding the anomalous condition. The sensor unit receives instructions to change operating parameters and/or control external devices.

Abstract: A sensor unit that includes at least one sensor configured to measure an ambient condition is described. The controller can be configured to receive instructions, to report a notice level when the controller determines that data measured by the at least one sensor fails a report threshold test corresponding to a report threshold value. The controller can also be configured to obtain a plurality of calibration measurements from the at least one sensor during a calibration period and to adjust the threshold based on the calibration measurements. The controller can be configured to compute a first threshold level corresponding to background noise and a second threshold level corresponding to sensor noise, and to compute the report threshold value from the second threshold. In one embodiment, the sensor unit adjusts one or more of the thresholds based on ambient temperature.