Abstract: In order to improve a method for selecting a frequency converter for a refrigerant compressor unit comprising a refrigerant compressor and an electric drive motor in such a way that the frequency converter is optimised for the application in question, it is proposed that a working state suitable for the operation of the refrigerant compressor unit is selected in an application field of an application diagram of the refrigerant compressor, that an operating frequency is selected for this selected working state, and that, on the basis of drive data, a working state operating current value corresponding to the selected working state and the selected operating frequency is ascertained for the operation of the refrigerant compressor unit.

Abstract: In order to improve a method for selecting a frequency converter for a refrigerant compressor unit comprising a refrigerant compressor and an electric drive motor in such a way that the frequency converter is optimised for the application in question, it is proposed that a working state suitable for the operation of the refrigerant compressor unit is selected in an application field of an application diagram of the refrigerant compressor, that an operating frequency is selected for this selected working state, and that, on the basis of drive data, a working state operating current value corresponding to the selected working state and the selected operating frequency is ascertained for the operation of the refrigerant compressor unit.

Abstract: A cooling circuit comprises a refrigerant compressor incorporating a suction port and a pressure chamber incorporating a pressure port, a condenser arranged downstream of the pressure port, a fluid collecting chamber in which a reservoir of refrigerant is formed, an evaporator which is located between the condenser and the suction port, a feed unit which is connected at one side to the refrigerant reservoir and to the pressure chamber at the other side and which serves for supplying refrigerant from the refrigerant reservoir to the pressure chamber which incorporates a pumping unit for the refrigerant. It is proposed that in order improve this cooling circuit, the pumping unit comprise a pressure-tight closed housing which is provided with only one inlet and one outlet as access points and a pumping element which is movable for pumping the refrigerant be arranged in the pumping chamber thereof.

Abstract: In order to improve a method for selecting a frequency converter for a refrigerant compressor unit that includes a refrigerant compressor and an electric drive motor such that the frequency converter is selected in a manner for optimized use, it is proposed that a working state suitable for operation of the refrigerant compressor unit should be selected within an application field of an application graph of the refrigerant compressor, that an operating frequency for this selected working state should be selected, and that a working state operating current value that corresponds to the selected working state and the selected operating frequency should be determined from drive data, for operation of the refrigerant compressor unit.

Abstract: In order to improve a method for selecting a frequency converter for a refrigerant compressor unit comprising a refrigerant compressor and an electric drive motor in such a way that the frequency converter is optimised for the application in question, it is proposed that a working state suitable for the operation of the refrigerant compressor unit is selected in an application field of an application diagram of the refrigerant compressor, that an operating frequency is selected for this selected working state, and that, on the basis of drive data, a working state operating current value corresponding to the selected working state and the selected operating frequency is ascertained for the operation of the refrigerant compressor unit

Abstract: In order to improve a method for selecting a frequency converter for a refrigerant compressor unit that includes a refrigerant compressor and an electric drive motor such that the frequency converter is selected in a manner for optimized use, it is proposed that a working state suitable for operation of the refrigerant compressor unit should be selected within an application field of an application graph of the refrigerant compressor, that an operating frequency for this selected working state should be selected, and that a working state operating current value that corresponds to the selected working state and the selected operating frequency should be determined from drive data, for operation of the refrigerant compressor unit.

Abstract: In a cooling circuit which comprises a refrigerant compressor incorporating a suction port and a pressure chamber incorporating a pressure port, a condenser which is arranged in the cooling circuit downstream of the pressure port and comprises a fluid collecting chamber in which a reservoir of refrigerant is formed, an evaporator which is located in the cooling circuit between the condenser and the suction port, a feed unit which is connected at one side to the refrigerant reservoir and to the pressure chamber at the other side and which serves for supplying refrigerant from the refrigerant reservoir to the pressure chamber which incorporates a pumping unit for the refrigerant, it is proposed that in order improve this cooling circuit in such a manner that it is realizable in an economically meaningful manner that the pumping unit comprise a pressure-tight closed housing which is provided with only one inlet and one outlet as access points and a pumping element which is movable for pumping the refrigerant be

Abstract: In order to improve a screw compressor comprising a housing, at least one screw rotor arranged in a compressor housing of the housing, a lubricant sump which is arranged on the high pressure side and in which lubricant collects, and a lubricant supply device which supplies lubricant from the lubricant sump to the at least one screw rotor, in such a manner that the amount of circulating lubricant can be kept as small as possible for adequate lubrication, it is suggested that the lubricant supply device comprise a first lubricant supply system and a second lubricant supply system, that the first lubricant supply system supply lubricant to the at least one screw rotor during operation of the screw compressor and that the second lubricant supply system additionally supply lubricant to the at least one screw rotor and thereby be activatable and deactivatable.

Abstract: In order to improve a screw compressor comprising a housing, at least one screw rotor arranged in a compressor housing of the housing, a lubricant sump which is arranged on the high pressure side and in which lubricant collects, and a lubricant supply device which supplies lubricant from the lubricant sump to the at least one screw rotor, in such a manner that the amount of circulating lubricant can be kept as small as possible for adequate lubrication, it is suggested that the lubricant supply device comprise a first lubricant supply system and a second lubricant supply system, that the first lubricant supply system supply lubricant to the at least one screw rotor during operation of the screw compressor and that the second lubricant supply system additionally supply lubricant to the at least one screw rotor and thereby be activatable and deactivatable.