Abstract: A sensor positioning device, having a holding module, with a sensor receptacle, fastening element and spring element, the sensor receptacle being mounted movably relative to the fastening element along a compensating axis. The spring is arranged between the fastening element and the sensor receptacle to cooperate therewith, to create a restoring force during movement of the receptacle relative to the fastening element. A measurement connector with an abutment is configured for arrangement onto a process container, and is configured for releasable arrangement on the holding module. The sensor positioning device is configured such that, when the measurement connector is arranged on the holding module, the sensor receptacle is movable relative to the fastening element along the axis, and a pressing force of the sensor receptacle onto the abutment of the measurement connector is created by the spring. A sensor unit, for turbidity measurement, is provided having the sensor positioning device.

Abstract: An immersion tube for a measuring probe of a type where a sensor element is arranged at the end of the measuring probe has a sleeve and an end piece. The end piece includes a plug, a connector piece, and a protector basket arranged between the plug and the connector piece. The connector piece connects the end piece to the sleeve and has an internal diameter that is enlarged relative to the internal diameter of the protector basket. The enlarged internal diameter portion ends at a circular internal step that can be seat for a sealing means, can provide a circular sealing lip, or both. A breakthrough opening on the protector basket is arranged perpendicular to the longitudinal axis of the immersion tube, whereby the sensor element which in operation is located in the protector basket can be brought into direct contact with a measurement medium. All surfaces and edges of the immersion tube which are exposed to the measurement medium during operation are smooth and rounded.

Abstract: An armature for holding an interchangeable measuring probe, has a housing (2), an immersion tube (3) that removably receives the probe and which is axially movable in the housing between a rest position and a measuring position, a drive mechanism arranged in a drive mechanism housing (17, 26), and a drive element (4) designed to be coupled to the immersion tube. The immersion tube and/or the measuring probe are always located outside of the drive mechanism housing. A housing attachment (25) is arranged between the housing and the drive mechanism housing, the housing attachment being connected to the housing in a releasable manner.

Abstract: An immersion tube for a measuring probe of a type where a sensor element is arranged at the end of the measuring probe has a sleeve and an end piece. The end piece includes a plug, a connector piece, and a protector basket arranged between the plug and the connector piece. The connector piece connects the end piece to the sleeve and has an internal diameter that is enlarged relative to the internal diameter of the protector basket. The enlarged internal diameter portion ends at a circular internal step that can be seat for a sealing means, can provide a circular sealing lip, or both. A breakthrough opening on the protector basket is arranged perpendicular to the longitudinal axis of the immersion tube, whereby the sensor element which in operation is located in the protector basket can be brought into direct contact with a measurement medium. All surfaces and edges of the immersion tube which are exposed to the measurement medium during operation are smooth and rounded.

Abstract: An armature for holding an interchangeable measuring probe, has a housing (2), an immersion tube (3) that removably receives the probe and which is axially movable in the housing between a rest position and a measuring position, a drive mechanism arranged in a drive mechanism housing (17, 26), and a drive element (4) designed to be coupled to the immersion tube. The immersion tube and/or the measuring probe are always located outside of the drive mechanism housing. A housing attachment (25) is arranged between the housing and the drive mechanism housing, the housing attachment being connected to the housing in a releasable manner.

Abstract: In order to remove waste water samples, particularly for photometric analysis, a quantity of filtrate is suctioned through a filtrate mesh (5) and a sample is removed therefrom and then analysed. The filtrate mesh (5) is purified in an intermittent manner in-between the removal of the samples. Said filtrate mesh (5) is electrically conductive and is impinged upon by a positive electric potential as an anode during the intermittent purifying steps in order to carry out anodic oxidation, during which a separated cathode (22, 34) is impinged upon by a negative electric potential. Said quantity of filtrate is suctioned into a filter chamber (2) through the filter mesh (5) by producing a depression. Said depression is essentially suppressed before and/or during the removal of the sample from the filter chamber (2).