A stuffing box for sealing a top opening of a vertical pump, including: a housing with a vertical tube for rotatably disposing a shaft of the vertical pump, an annular bearing that: divides the vertical tube in a lower half and an upper half, and fills an annular space between an inner wall of the vertical tube and the shaft, such that as less fluid as possible passes from the lower half through the annular bearing to the upper half, an outlet pipe for discharging the fluid passing through the annular bearing.

A stuffing box for sealing a top opening of a vertical pump, including: a housing with a vertical tube for rotatably disposing a shaft of the vertical pump, an annular bearing that: divides the vertical tube in a lower half and an upper half, and fills an annular space between an inner wall of the vertical tube and the shaft, such that as less fluid as possible passes from the lower half through the annular bearing to the upper half, an outlet pipe for discharging the fluid passing through the annular bearing.

A method and controller for controlling electrical activation of elements in a system. A method includes identifying (710) a first element (102) of a system (100) by a control system (600), among a plurality of elements (102, 110, 122) of the system (100), that is to be powered. The method includes determining (712) connected elements (110, 122) of the system (100) by the control system (600). The connected elements (110, 122) are connected to deliver power to the first element (102) directly or indirectly, based on an adjacency matrix (400), and the adjacency matrix (400) identifies connections between each of plurality of elements of the system (100). The method includes identifying (714) at least one of the connected elements (110, 122) to activate by the control system (600), based on the adjacency matrix (400), a health table (500), and the connected elements (110, 122), to deliver power to the first element (102). The method includes activating (716) the at least one of the connected elements (110, 122) by the control system (600), thereby delivering power to the first element (102).

A method and controller for controlling electrical activation of elements in a system. A method includes identifying (710) a first element (102) of a system (100) by a control system (600), among a plurality of elements (102, 110, 122) of the system (100), that is to be powered. The method includes determining (712) connected elements (110, 122) of the system (100) by the control system (600). The connected elements (110, 122) are connected to deliver power to the first element (102) directly or indirectly, based on an adjacency matrix (400), and the adjacency matrix (400) identifies connections between each of plurality of elements of the system (100). The method includes identifying (714) at least one of the connected elements (110, 122) to activate by the control system (600), based on the adjacency matrix (400), a health table (500), and the connected elements (110, 122), to deliver power to the first element (102). The method includes activating (716) the at least one of the connected elements (110, 122) by the control system (600), thereby delivering power to the first element (102).

A compressor or pump stage is provided. The compressor or pump stage at least comprising a central shaft (8) and one rotor (3), where the axis of rotation of the rotor (3) is the central shaft (8) and where the rotor comprises a number, n, of rows of impellers (5) arranged at an outer perimeter of the rotor with an axial distance between neighbouring rows of impellers (5), where n={2, 3, 4...}.

A compressor or pump stage is provided. The compressor or pump stage at least comprising a central shaft (8) and one rotor (3), where the axis of rotation of the rotor (3) is the central shaft (8) and where the rotor comprises a number, n, of rows of impellers (5) arranged at an outer perimeter of the rotor with an axial distance between neighbouring rows of impellers (5), where n={2, 3, 4...}.

A method serves for operating an electronically controlled pump assembly (1), with which setting parameters of the pump (2) can be adjusted in an electronic control (6), for adaptation to the hydraulic demands of the location installation situation (4, 5). Operating data is registered during the operation of the pump assembly (1). After a predefined time and on the basis of the registered operating data, it is examined as to whether the pump assembly (1) has been set vis-à-vis the factory settings. If this is not the case a signal (11) is issued in order to point out the necessary setting.

A method serves for operating an electronically controlled pump assembly (1), with which setting parameters of the pump (2) can be adjusted in an electronic control (6), for adaptation to the hydraulic demands of the location installation situation (4, 5). Operating data is registered during the operation of the pump assembly (1). After a predefined time and on the basis of the registered operating data, it is examined as to whether the pump assembly (1) has been set vis-à-vis the factory settings. If this is not the case a signal (11) is issued in order to point out the necessary setting.

A pump assembly is disclosed comprising, a pump including a pump housing having a fluid inlet. At least one fluid outlet extends from the pump housing. An impeller driven by a motor is mounted in the pump housing arranged to move a fluid from the fluid inlet to the at least one fluid outlet. A valve rotatably mounted between the impeller and the at least one fluid outlet selectively controls the flow of fluid through the at least one fluid outlet.

A compressor control apparatus includes a rectifier configured to rectify AC power to DC power; an inverter including a plurality of switching elements, configured to convert the DC power into a three-phase voltage according to a pulse width modulation (PWM) signal applied to the plurality of switching elements; a motor configured to receive a three-phase current based on the three-phase voltage; a current detector configured to detect a sum of a first phase current, a second phase current, and a third phase current supplied to the motor; and a controller configured to differently determine a duty ratio of the PWM signal applied to each of the plurality of switching elements, and to determine the first phase current, the second phase current, and the third phase current, respectively, based on the determined duty ratio and the sum of the currents detected from the current detector.