An air-conditioning apparatus includes an indoor unit and an outdoor unit including a compressor that compresses a refrigerant and a motor drive system that drives the compressor. The motor drive system includes an inverter that converts a DC voltage into an AC voltage, and an electric motor including three stator windings with both ends open. The electric motor operates based on the AC voltage obtained by the inverter. The motor drive system further includes a connection state switching unit that has a function to change the connection state of the three stator windings included in the electric motor, and sets the connection state to a star connection at the start of operation of the air-conditioning apparatus.

A pump apparatus and a pump apparatus monitoring system are disclosed. The pump apparatus monitoring system includes a cloud server, a remote electronic device, a near end electronic device and a pump apparatus. The pump apparatus includes a control module and at least one parameter sensor. The parameter sensor is for sensing at least one parameter of the pump apparatus. The control module transmits the at least one parameter to the near end electronic device. The near end electronic device uploads the at least one parameter to the cloud server via a network. The remote electronic device downloads the at least one parameter from the cloud server via the network. Accordingly, staff at the remote end is able to get parameters of the pump apparatus by the remote electronic device, so as to adjust the pump apparatus.

A beverage syrup pump system is disclosed including a pump housing having an internal pumping chamber, a pump motor, and a pumping mechanism driven by the motor within the pumping chamber. The pumping mechanism receives a syrup fluid at a first pressure and discharges the fluid at a second pressure which is greater than the first pressure. A pressure transducer adjacent a sensor port and in contact with a quantity of the fluid at the second pressure generates an electrical signal based upon the second pressure. A programmable micro controller receives the electrical signal from the pressure transducer and is capable of starting and stopping the pump motor. The micro controller will immediately stop the pump motor if the second pressure exceeds a predetermined maximum pressure level. The micro controller will also stop the pump motor if the second pressure falls and remains below a predetermined minimum pressure level for a predetermined first time interval.

A beverage syrup pump system is disclosed including a pump housing having an internal pumping chamber, a pump motor, and a pumping mechanism driven by the motor within the pumping chamber. The pumping mechanism receives a syrup fluid at a first pressure and discharges the fluid at a second pressure which is greater than the first pressure. A pressure transducer adjacent a sensor port and in contact with a quantity of the fluid at the second pressure generates an electrical signal based upon the second pressure. A programmable micro controller receives the electrical signal from the pressure transducer and is capable of starting and stopping the pump motor. The micro controller will immediately stop the pump motor if the second pressure exceeds a predetermined maximum pressure level. The micro controller will also stop the pump motor if the second pressure falls and remains below a predetermined minimum pressure level for a predetermined first time interval.

An embodiment of a system with a minute measure of pulsatility in a flow of a fluid is described that comprises a first pump configured to flow the fluid to a junction at a first flow rate that comprises a measure of pulsatility; and a second pump configured to flow a portion of the fluid from the junction at a second flow rate that is less than the first flow rate to produce a flow of the fluid at a third flow rate from the junction with a minute measure of pulsatility.

A simpler notification is given about identifying causes of abnormalities and indicating dealing methods or countermeasures to deal with the causes of abnormalities. In a gas compressor including: a compressor body that compresses a gas; a drive source that drives the compressor body; at least one physical sensor that is disposed on at least one of a compressed-gas pipe or an electric system and detects a physical quantity in driving of the compressor body; a display unit; and a controller that processes the detected result from the physical sensor and causes the display unit to display information according to the processing, the controller stores in advance the associated relation between a preset range with respect to a rate of change of the physical quantity and information about at least one of a cause of a change in the physical quantity and a dealing method of dealing the cause, calculates a rate of change of the physical quantity on the basis of the detected result from the physical sensor, and causes the display unit to display information about at least one of the cause corresponding to the preset range and the dealing method of dealing with the cause when the calculated rate of change of the physical quantity is determined as falling in the preset range.