A method is provided for controlling and/or monitoring a compressor system comprising several components, namely one or more compressors, one or more peripheral devices, and also a control/monitoring unit, wherein the compressors and peripheral devices are arranged or connected in a certain configuration. The method distinguishes itself in that (a) in a measured-value-capture step, measured values are captured within the compressor system or the components; (b) in an allocation step, context information is allocated to the measured value or measured values in advance, simultaneously, or after the measured-value capture, in order to standardize the measured values; and (c) in an evaluation step, the measured value or measured values standardized by the context information are used in a control, monitoring, diagnostics, or evaluation routine.

In a refrigerant compressor for refrigeration plants, comprising a compressor unit driven by a drive unit, wherein at least one of these units is provided with a control unit which is controllable by means of a delivery rate control system in order to control the refrigerant compressor at different delivery rates, wherein an external delivery rate setpoint value is communicated to the delivery rate control system, in order to prevent critical operating states, it is proposed that the delivery rate control system acquires, by means of a sensor, a compressor reference temperature of the compressor unit, that the delivery rate control system ascertains an operating state value group for the acquisition of an operating state of the refrigerant compressor and, taking account of specified reference values, if the value of the ascertained operating state value group based upon the compressor reference temperature permits a critical operating state of the refrigerant compressor, specifies a delivery rate which has as its result an operation of the refrigerant compressor outside of the critical operating states.

A digital pressure switch is configured to be connected to a fluid pump. The digital pressure switch includes a pressure sensor configured to measure pressure inside a closed system, one or more relays configured to be connected to the fluid pump for activation and deactivation of the fluid pump, an amperage sensor configured to measure an amperage draw of an electric motor of the fluid pump, and a controller configured to process data from the pressure sensor and/or data from the amperage sensor and to activate or deactivate the motor of the fluid pump based on the data from the pressure sensor and/or the data from the amperage sensor, using the relays.

A vane for use in a rotary vane pump. The vane has a length L extending between a first edge of the vane and a second edge of the vane and a width W extending perpendicular to said length, the width extending between a third edge of said vane and a fourth edge of the vane, and further comprising a channel extending through said vane and provided at a position along said length L of said vane. The channel maybe positioned away from said first and second edges such that said vane has a constant length L along its width. The width of the channel may vary in shape between first and second points along the length of the vane. The channel may have a triangular shape, a rectangular shape or a circular shape. A method for detecting the decrease in length of the vane is also described.

A compressor fault diagnostic apparatus including a current sensing unit to sense a current flowing through a motor of the compressor, a fault diagnostic unit to determine whether or not the motor performs a reverse rotation based on the current flowing through the motor, and a cut-off unit to remove power based on a determination of the fault diagnostic unit.

A method for controlling a permanent magnet (PM) synchronous motor in an ESP application is provided. A load angle of the PM motor is estimated. A voltage adjustment value is determined for the PM motor based at least on the estimated load angle of the PM motor. A voltage to be applied to the PM motor is determined based on the voltage adjustment value.

A method for controlling a permanent magnet (PM) synchronous motor in an ESP application is provided. A load angle of the PM motor is estimated. A voltage adjustment value is determined for the PM motor based at least on the estimated load angle of the PM motor. A voltage to be applied to the PM motor is determined based on the voltage adjustment value.

The invention relates to a method for controlling and/or monitoring a compressor system comprising several components, namely one or more compressors (11, 12, 13) and one or more peripheral devices (14 to 21), and also a control/monitoring unit (22), wherein the compressors (11, 12, 13) and peripheral devices (14 to 21) are arranged or connected in a certain configuration. The method distinguishes itself in that in a measured-value-capture step, measured values are captured within the compressor system or the components, in an allocation step, context information is allocated to the measured value or measured values in advance, simultaneously, or after the measured-value capture, in order to standardize the measured values, and in an evaluation step, the measured value or measured values standardized by the context information is used in a control, monitoring, diagnostics, or evaluation routine.

A method of monitoring a volume index valve of a compressor is provided. The method includes recording a first reading of an operating condition of the compressor when the volume index valve is in a first position. The method also includes switching the volume index valve to a second position. The method further includes recording a second reading of the operating condition of the compressor when the volume index valve is in the second position. The method yet further includes calculating a difference between the first reading and the second reading. The method also includes comparing the difference to a predetermined threshold difference to determine if the volume index valve is moving between the first position and the second position in a desired manner.

A fluid machine device includes a plurality of fluid machines that discharge a fluid; a worn state detection unit that detects a worn state of the fluid machine; a pressure detection unit that measures a pressure from the fluid machines; and a control unit that controls the plurality of fluid machines. The control unit determines whether or not there is the fluid machine that is worn, and performs control to start operation of the fluid machine that is not worn when the pressure is insufficient.