A pressure sensor includes: a detection device for ascertaining air pressure and temperature; a computing unit; and a wireless interface. With the aid of the wireless interface, the pressure sensor data which represent a flow state in the surroundings of the pressure sensor are transferred wirelessly to a central control device. With the aid of the central control device, final control elements of a ventilation device are set.

A system and a method that utilizes wet proppants when creating fracturing fluid by receiving wet fracturing sand at a surge tank, vibrating the wet fracturing sand located within the surge tank, liquefying the wet fracturing sand within the surge tank based on the vibration, and metering the liquefied wet fracturing sand from the surge tank to a blending tub.

Sensor-mounting devices are disclosed. A sensor mounting device has a tubular body having a front end, a rear end, and a through hole that extends between the front and rear ends. The tubular body front end includes a flange with a perimeter that is larger than a perimeter of the tubular body. The flange may be positioned at a front face of a mounting structure. A sensor-attachment structure is located on at least one of the tubular body and the front flange. Further locking structure extends from the tubular body to couple the tubular body to the mounting structure. The locking structure is at least one item from the group consisting of: a rear flange, a barb, and threading.

A method for operating and/or monitoring an HVAC system (10), in which a medium circulating in a primary circuit (26) flows through at least one energy consumer (11, 12, 13), the medium entering with a volume flow () through a supply line (14) into the energy consumer (11, 12, 13) at a supply temperature (T.sub.v) and leaving the energy consumer (11, 12, 13) at a return temperature (T.sub.R) via a return line (15), and transferring heat or cooling energy to the energy consumer (11, 12, 13) in an energy flow (E). A control unit (21) adaptively operates the system by empirically determining the dependence of the energy flow (F) and/or the temperature difference T between supply temperature (T.sub.v) and return temperature (T.sub.R) on the volume flow () for the energy consumers (11, 12, 13) in a first step, and by operating and/or monitoring the HVAC system (10) according to the determined dependency or dependencies in a second step.

Embodiments of the disclosure describe a robust optical monitoring device and an operating method thereof. The optical monitoring device includes a housing comprising a first compartment and a second compartment. The first compartment includes a camera circuit board and a wireless connection circuit board, wherein the second compartment comprises a supply circuit board. Further, the housing includes an isolation cell to isolate the first compartment and the second compartment, a camera configured to be disposed in the first compartment of the housing to receive images associated with a sight glass, and an illumination board disposed within the first compartment of the housing positioned to project light for operation of the camera.

A health monitoring system of an aircraft includes a plurality of sensors and interfaces that are non-invasively installed in a system of the aircraft. Further, the health monitoring system includes a data concentrator unit that is coupled to the plurality of sensor and interfaces. The data concentrator unit receives data associated with various components of the aircraft system from the plurality of sensor and interfaces. Responsively, the data concentrator unit processes the received data to generate a single output data stream that is transmitted to a configurable data receiver unit of the aircraft. The configurable data receiver unit transmits the received single output data stream to a ground server and an on-board display to monitor and determine a health and/or performance of the aircraft system.

A power monitoring system includes a plurality of current sensors suitable to sense respective changing electrical current within a respective conductor to a respective load and a conductor sensing a respective voltage potential provided to the respective load. A power monitors determines a type of circuit based upon a signal from at least one of the current sensors and a signal from the conductor, wherein the type of circuit includes at least one of a single phase circuit, a two phase circuit, and a three phase circuit. The power meter configures a set of registers corresponding to the determined type of circuit in a manner such that the configuring is different based upon each of the single phase circuit, two phase circuit, and three phase circuit suitable to provide data corresponding to the determined type of circuit.

A monitoring system for a heating, ventilation, or air conditioning (HVAC) system of a residential or commercial building includes an evaporator unit device and four temperature sensors. The evaporator unit device includes an electrical sensor that measures current supplied to a circulator blower of the HVAC system. The measured current from the first electrical sensor is used to diagnose a problem with the circulator blower. The first temperature sensor that measures a temperature of refrigerant flowing between a condenser of the HVAC system and an expansion valve of the HVAC system. The second temperature sensor measures a temperature of refrigerant flowing between an evaporator and a compressor. The third temperature sensor measures a temperature of air flowing away from the evaporator. The fourth temperature sensor measures a temperature of air flowing toward the evaporator. The evaporator unit device transmits sensor data to a remote monitoring service over a data network.

The invention relates to a method for operating and/or monitoring an HVAC system (10), in which medium circulating in a primary circuit (26) flows through at least one energy consumer (11, 12, 13), the medium entering with a volume flow () through a supply line (14) into the energy consumer (11, 12, 13) at a supply temperature (T.sub.V) and leaving the energy consumer (11, 12, 13) at a return temperature (T.sub.R) via a return line (15), and transferring heat or cooling energy to the energy consumer (11, 12, 13) in an energy flow (E). A considerable improvement in the operating behavior of the system is achieved by empirically determining the dependence of the energy flow (E) and/or the temperature difference (AT) between supply temperature (T.sub.V) and return temperature (T.sub.R) on the volume flow () for the energy consumers (11, 12, 13) in a first step, and by operating and/or monitoring the HVAC system (10) according to the determined dependency or dependencies in a second step.

In a device and method for taking temperature readings on an HVAC system, a first probe is connectable in thermal communication with the HVAC system for taking a first temperature reading thereof. A second probe is connectable in thermal communication with the HVAC system for taking a second temperature reading thereof that is independent of the first temperature reading. A digital display is connectable to the first and second probes for displaying the first and second temperature readings.