Abstract: The present disclosure relates an interface unit having an input for receiving an input voltage from an electrochemical measuring probe; a first transistor; a first operational amplifier; a second transistor; and a second operational amplifier. The first operational amplifier is arranged to provide a variable tension to a first source terminal of the first transistor, in accordance with a comparison between a reference voltage and a second resistor voltage, in order to control an operating point of the first transistor.

Abstract: The present disclosure relates an interface unit having an input for receiving an input voltage from an electrochemical measuring probe; a first transistor; a first operational amplifier; a second transistor; and a second operational amplifier. The first operational amplifier is arranged to provide a variable tension to a first source terminal of the first transistor, in accordance with a comparison between a reference voltage and a second resistor voltage, in order to control an operating point of the first transistor.

Abstract: The operation of a measuring probe used for measuring at least one property of a process material is monitored or determined while the measuring probe is in use. The measured property can be a pH measurement, or a CO2 or oxygen concentration of the process material. The measuring probe has an electrode with a sensing element. When the sensing element is in contact with the process material, the electrode delivers a measurement signal to the measurement signal circuit, where the electrode voltage is related to the measured property. The signal-processing unit determines a measurement quantity of the measured property using the measurement signal. When a test signal is delivered by the signal source to the test signal circuit during a verification phase, a coupling element ensures galvanic isolation between the measurement signal circuit and the test signal circuit.

Abstract: The operation of a measuring probe used for measuring at least one property of a process material is monitored or determined while the measuring probe is in use. The measured property can be a pH measurement, or a CO2 or oxygen concentration of the process material. The measuring probe has an electrode with a sensing element. When the sensing element is in contact with the process material, the electrode delivers a measurement signal to the measurement signal circuit, where the electrode voltage is related to the measured property. The signal-processing unit determines a measurement quantity of the measured property using the measurement signal. When a test signal is delivered by the signal source to the test signal circuit during a verification phase, a coupling element ensures galvanic isolation between the measurement signal circuit and the test signal circuit.

Abstract: To determine whether stress cracks are present in the bottom area of a plastic bottle which make it unfit for further use, the bottle bottom is scanned in the potential crack region by the measuring beam of a laser distance-measuring instrument. From its output signal, the prevalence and depth of the cracks can be identified sufficiently to enable a decision to be made on the removal of the bottle from circulation.