Abstract: HVAC components having improved efficiency are described. In one embodiment, excessive sleep current draw in a battery-powered device having a microcontroller is detected by measuring a voltage drop across a MOSFET device coupled in a for ward-conducting orientation in series between the battery and the microcontroller, causing a transistor to conduct when the voltage drop exceeds a predetermined threshold to generate a first trigger signal, integrating the first trigger signal to generate a second trigger signal, and generating an interrupt to the microcontroller. In another embodiment, a battery-saving method of operating an HVAC component includes maintaining the HVAC device in the sleep mode, receiving a user input to wake the device, transmitting a data request and returning the HVAC component to the sleep mode, waking up the HVAC device to poll an adjacent network node storing a cached response, displaying the response, and returning the HVAC device to sleep.

Abstract: Devices and methods use an Extended Permanent Account Number Identification (EPID) of a mesh network (e.g., ZigBee) to include in the EPID a network information, a network channel information (e.g., 802.15.4 channel), and/or other data. The devices and methods allows a node to use the EPID to identify a desired network to join and join the network on the predetermined channel for that network.

Abstract: Devices and methods use an Extended Permanent Account Number Identification (EPID) of a mesh network (e.g., ZigBee) to include in the EPID a network information, a network channel information (e.g., 802.15.4 channel), and/or other data. The devices and methods allows a node to use the EPID to identify a desired network to join and join the network on the predetermined channel for that network.

Abstract: HVAC components having improved efficiency are described. In one embodiment, excessive sleep current draw in a battery-powered device having a microcontroller is detected by measuring a voltage drop across a MOSFET device coupled in a forward-conducting orientation in series between the battery and the microcontroller, causing a transistor to conduct when the voltage drop exceeds a predetermined threshold to generate a first trigger signal, integrating the first trigger signal to generate a second trigger signal, and generating an interrupt to the microcontroller. In another embodiment, a battery-saving method of operating an HVAC component includes maintaining the HVAC device in the sleep mode, receiving a user input to wake the device, transmitting a data request and returning the HVAC component to the sleep mode, waking up the HVAC device to poll an adjacent network node storing a cached response, displaying the response, and returning the HVAC device to sleep.

Abstract: A computer implemented method for automatically switching communication protocols. The method includes detecting a user input, determining, based on the user input, a first communication protocol needed to address the user input, and creating a virtualized network wherein devices that use a second communication protocol are represented via virtualized devices according to the first communication protocol.

Abstract: Embodiments described herein provide a method of fragmenting a large message into, for example, numbered packets for sending the message in a packet based communication system, such as in a ZigBee wireless network. Each packet may have a predetermined size and may include a MAC address, a network header of a variable size, and fragmented message data. The fragmented message data can be configured to be smaller than the available space in the packet so that the packet can be sent, for example, when the size of the header increases.

Abstract: Devices and methods use an Extended Permanent Account Number Identification (EPID) of a mesh network (e.g., ZigBee) to include in the EPID a network information, a network channel information (e.g., 802.15.4 channel), and/or other data. The devices and methods allows a node to use the EPID to identify a desired network to join and join the network on the predetermined channel for that network.

Abstract: Devices and methods use an Extended PAN Identification (EPID) of a mesh network (e.g., ZigBee) to include in the EPID a network information, a network channel information (e.g., 802.15.4 channel), and/or other data. The devices and methods allows a node to use the EPID to identify a desired network to join and join the network on the predetermined channel for that network.

Abstract: Embodiments described herein provide a method of fragmenting a large message into, for example, numbered packets for sending the message in a packet based communication system, such as in a ZigBee wireless network. Each packet may have a predetermined size and may include a MAC address, a network header of a variable size, and fragmented message data. The fragmented message data can be configured to be smaller than the available space in the packet so that the packet can be sent, for example, when the size of the header increases.

Abstract: Embodiments described herein provide a method of fragmenting a large message into, for example, numbered packets for sending the message in a packet based communication system, such as in a ZigBee wireless network. Each packet may have a predetermined size and may include a MAC address, a network header of a variable size, and fragmented message data. The fragmented message data can be configured to be smaller than the available space in the packet so that the packet can be sent, for example, when the size of the header increases.

Abstract: Devices and computer-implemented methods for controlling data communication to one or more devices in a network, e.g., a mesh network. The methods include a device broadcasting data requested by a first device, and a second device eavesdropping on the broadcast of the data in order to capture the data and to storing the captured data if the data is appropriate for the second device.

Abstract: Systems and methods for a network, wherein a network device sends one or more pieces of a fragmented message to another network device via a network, and the network device that has received the one or more pieces of the fragmented messaging sends one or more acknowledgments of the receipt of the one or more pieces of the fragmented message to the sender of the fragmented message.

Abstract: Device and method for detecting and visualizing a wireless network health and/or health of network devices connected to the wireless network. The wireless network health is detected based on one or more link quality indication (LQI) to indicate the strength of the communication link between the network devices. The wireless network health is displayed in a visualization on a computer display in real time or near real time so that the quality of the wireless network communication and health of the network devices can be quickly and easily understood by a user.

Abstract: Devices and methods use an Extended Permanent Account Number Identification (EPID) of a mesh network (e.g., ZigBee) to include in the EPID a network information, a network channel information (e.g., 802.15.4 channel), and/or other data. The devices and methods allows a node to use the EPID to identify a desired network to join and join the network on the predetermined channel for that network.

Abstract: Embodiments described herein provide a method of fragmenting a large message into, for example, numbered packets for sending the message in a packet based communication system, such as in a ZigBee wireless network. Each packet may have a predetermined size and may include a MAC address, a network header of a variable size, and fragmented message data. The fragmented message data can be configured to be smaller than the available space in the packet so that the packet can be sent, for example, when the size of the header increases.

Abstract: Two vertically offset thermistors for sensing a fluid such as oil and refrigerant in a compressor shell are monitored by a method that takes into account rapidly changing conditions within the shell. The system can determine the fluid's sump temperature, high/low liquid levels, and can determine whether the thermistors are sensing the fluid as a liquid, gas, or a mixture of the two, such as a foam or mist of liquid and gas. For greater accuracy, thermistor readings can be dithered and filtered to provide temperature or voltage values having more significant digits than the readings originally processed through a limited-bit A/D converter. For faster response, limited microprocessor time is conserved by sampling thermistor readings at strategic periods that enable the microprocessor to identify certain conditions and temperatures via simple delta-temperature ratios and undemanding equations rather than resorting to exponential functions or lookup tables to determine time constants.

Abstract: Two vertically offset thermistors for sensing a fluid such as oil and refrigerant in a compressor shell are monitored by a method that takes into account rapidly changing conditions within the shell. The system can determine the fluid's sump temperature, high/low liquid levels, and can determine whether the thermistors are sensing the fluid as a liquid, gas, or a mixture of the two, such as a foam or mist of liquid and gas. For greater accuracy, thermistor readings can be dithered and filtered to provide temperature or voltage values having more significant digits than the readings originally processed through a limited-bit A/D converter. For faster response, limited microprocessor time is conserved by sampling thermistor readings at strategic periods that enable the microprocessor to identify certain conditions and temperatures via simple delta-temperature ratios and undemanding equations rather than resorting to exponential functions or lookup tables to determine time constants.

Abstract: A method of controlling a refrigerant chiller system is particularly suited for chillers where the water being chilled (or some other liquid) flows through the chiller's evaporator at a flow rate that is variable and is not directly known. To effectively control the chiller and maintain the temperature of the water leaving the evaporator at a desired target temperature, the cooling capacity of the chiller's evaporator is estimated based the degree of valve opening of an expansion valve, a pressure differential across the expansion valve, and a change in enthalpy per unit mass of the refrigerant flowing through the evaporator. In some embodiments, the chiller system includes multiple refrigerant circuits that are hermetically isolated from each other.

Abstract: A control method regulates an electronic expansion valve of a chiller to maintain the refrigerant leaving a DX evaporator at a desired or target superheat that is minimally above saturation. The expansion valve is controlled to convey a desired mass flow rate, wherein valve adjustments are based on the actual mass flow rate times a ratio of a desired saturation pressure to the suction pressure of the chiller. The suction temperature helps determine the desired saturation pressure. A temperature-related variable is asymmetrically filtered to provide the expansion valve with appropriate responsiveness depending on whether the chiller is operating in a superheated range, a saturation range, or in a desired range between the two.

Abstract: Two vertically offset thermistors for sensing a fluid such as oil and refrigerant in a compressor shell are monitored by a method that takes into account rapidly changing conditions within the shell. The system can determine the fluid's sump temperature, high/low liquid levels, and can determine whether the thermistors are sensing the fluid as a liquid, gas, or a mixture of the two, such as a foam or mist of liquid and gas. For greater accuracy, thermistor readings can be dithered and filtered to provide temperature or voltage values having more significant digits than the readings originally processed through a limited-bit A/D converter. For faster response, limited microprocessor time is conserved by sampling thermistor readings at strategic periods that enable the microprocessor to identify certain conditions and temperatures via simple delta-temperature ratios and undemanding equations rather than resorting to exponential functions or lookup tables to determine time constants.