Abstract: A building management system includes a communications interface connected to HVAC devices, a device identifier configured to identify the HVAC devices, a fault detector configured to detect a fault condition in the identified devices, and a causal relationship template retriever configured to retrieve a fault causation template of system parameters specific to the fault condition. The building management system further includes a status requestor configured to retrieve operating data from the identified devices and a user interface generator. The user interface generator is configured to populate the system parameters of the fault causation template with the retrieved operating data and transmit a signal to display a user interface with the populated fault causation template on a display screen.

Abstract: A thermostat for transmitting data wirelessly to a controller in a building includes a temperature sensor, a processing circuit, and a wireless radio. The processing circuit is configured to receive a measured temperature value from the temperature sensor, determine a current temperature error based on the current measured temperature value and a setpoint temperature, and determine whether a difference between the current temperature error and a previous temperature error is greater than an error threshold. The processing circuit is configured to determine whether a minimum amount of time has passed since transmitting a previous measured temperature value and transmit the current measured temperature value to the controller via the wireless transmitter in response to determining that both the difference between the current temperature error and the previous temperature error is greater than the error threshold and the minimum amount of time has passed since transmitting a temperature value.

Abstract: A building management system includes a communications bus, an old master controller device; and slave devices. The slave devices are configured to detect that the old master controller device has stopped communicating over the communications bus and to perform an algorithm to determine a new master controller device from the slave devices. The algorithm is based on a device identifier associated with each of the slave devices. The new master controller device is further configured to assume the functions of the master controller device. The functions of the master controller device include transmitting control signals to the slave devices.

Abstract: A chilled water plant includes a communications bus, chilled water plant devices connected to the communications bus, and a chiller device connected to the communications bus. The chiller device is configured to detect the chilled water plant devices connected to the communications bus during a commissioning process, determine device status modules based at least in part on a type of each of the chilled water plant devices, control an operation of the chilled water plant, and display a user interface containing the device status modules.

Abstract: A building management system includes a communications bus, slave devices connected to the communications bus, a remote server that includes a slave device configuration database, and a master controller connected to the communications bus. The master controller is configured to query the slave devices for device identification codes, receive device identification codes from the slave devices, and connect to the remote server. The master controller is further configured to transmit device identification codes to the slave device configuration database, receive slave device configuration information from the slave device configuration database, and control the slave devices based on the slave device configuration information.

Abstract: A fault detection and diagnostics (FDD) system is provided for a refrigeration circuit having an evaporator and a compressor configured to circulate a refrigerant through the evaporator. The FDD system includes a communications interface configured to receive a measurement of a thermodynamic property affected by the refrigeration circuit and a processing circuit having a processor and memory. The processing circuit is configured to use the measured thermodynamic property to determine an expected suction entropy of the refrigerant at a suction of the compressor, use the expected suction entropy to determine an expected thermodynamic discharge property of the refrigerant at a discharge of the compressor, determine an actual thermodynamic discharge property of the refrigerant at the discharge of the compressor, and detect a fault in the refrigeration circuit by comparing the expected thermodynamic discharge property with the actual thermodynamic discharge property.

Abstract: Systems and methods for automated fault detection in a building management system are shown and described. The systems and methods further involve organizing the data set into bins, each bin containing a plurality of the observed points for the variable of the building management system. The systems and methods further involve calculating, for each bin, a target parameter and an estimator of scale for the observed points. The systems and methods further involve detecting, for each bin, an outlier of the building management system by comparing a data point of the bin to the calculated target parameter and estimator of scale for the bin.

Abstract: Systems and methods for estimating a flow rate through a device are provided. One or more pressure sensors measure a plurality of pressure differentials across a tested device. A temporary flow rate sensor measures a plurality of flow rates through the tested device. Each of the measured flow rates corresponds to one of the measured pressure differentials. A regression model trainer generates regression coefficients for a flow rate model using the measured pressure differentials and corresponding flow rates. A flow rate estimator uses the flow rate model to estimate a flow rate through a tested or untested device as a function of a measured pressure differential across the tested or untested device.

Abstract: A fault detection and diagnostics (FDD) system is provided for a refrigeration circuit having an evaporator and a compressor configured to circulate a refrigerant through the evaporator. The FDD system includes a communications interface configured to receive a measurement of a thermodynamic property affected by the refrigeration circuit and a processing circuit having a processor and memory. The processing circuit is configured to use the measured thermodynamic property to determine an expected suction entropy of the refrigerant at a suction of the compressor, use the expected suction entropy to determine an expected thermodynamic discharge property of the refrigerant at a discharge of the compressor, determine an actual thermodynamic discharge property of the refrigerant at the discharge of the compressor, and detect a fault in the refrigeration circuit by comparing the expected thermodynamic discharge property with the actual thermodynamic discharge property.

Abstract: A fault parameter of an energy consumption model is modulated. The energy consumption model is used to estimate an amount of energy consumption at various values of the fault parameter. A first set of variables is generated including differences between a target value of the fault parameter and the various values of the fault parameter. A second set of variables is generated including differences between an estimated amount of energy consumption with the fault parameter at the target value and the estimated amounts of energy consumption with the fault parameter at the various values. The first set of variables and second set of variables are used to develop a regression model for the fault parameter. The regression model estimates a change in energy consumption based on a change in the fault parameter. Regression models are developed for multiple fault parameters and used to prioritize faults.

Abstract: Systems and methods for automated fault detection in a building management system are shown and described. The systems and methods further involve organizing the data set into bins, each bin containing a plurality of the observed points for the variable of the building management system. The systems and methods further involve calculating, for each bin, a target parameter and an estimator of scale for the observed points. The systems and methods further involve detecting, for each bin, an outlier of the building management system by comparing a data point of the bin to the calculated target parameter and estimator of scale for the bin.