Abstract: The present invention relates to a method of proof-testing a radar level gauge system arranged to determine a filling level of a product in a tank, the method comprising the steps of: transmitting an electromagnetic transmit signal towards a surface of the product in the tank; receiving an electromagnetic reflection signal resulting from reflection of the transmit signal at the surface of the product; forming a measurement representation based on the transmit signal and the reflection signal, the measurement representation comprising surface echo information indicative of the filling level of the product; adding, to the measurement representation, proof test echo information indicative of a predefined proof test level, resulting in a modified measurement representation; processing the modified measurement representation to determine a proof test level based on the modified measurement representation; and providing a signal indicative of a result of the processing.

Abstract: The present invention relates to a method of proof-testing a radar level gauge system arranged to determine a filling level of a product in a tank, the method comprising the steps of: transmitting an electromagnetic transmit signal towards a surface of the product in the tank; receiving an electromagnetic reflection signal resulting from reflection of the transmit signal at the surface of the product; forming a measurement representation based on the transmit signal and the reflection signal, the measurement representation comprising surface echo information indicative of the filling level of the product; adding, to the measurement representation, proof test echo information indicative of a predefined proof test level, resulting in a modified measurement representation; processing the modified measurement representation to determine a proof test level based on the modified measurement representation; and providing a signal indicative of a result of the processing.

Abstract: The present invention relates to a radar level gauge (10) for determining a filling level (L) of a product in a tank, said radar level gauge comprising a Bluetooth communication unit, wherein the Bluetooth protocol is the sole communication protocol of the radar level gauge, and wherein the radar level gauge is devoid of any communication terminal(s) and associated components adapted to connect the radar level gauge to an external communication device via at least one communication wire.

Abstract: A field device for determining a process parameter value, comprising a measurement device for determining a process parameter value; circuitry for determining the reliability of the process parameter value; and signaling circuitry for providing the process parameter value and an indication of the reliability of the process parameter value to a host system via a current loop. The signaling circuitry is configurable between a first state in which the indication of the reliability is provided as a digital signal and the process parameter value is provided as an analog DC-value, and a second state in which the indication of the reliability is provided as a predetermined analog DC-value. Hereby, the number of unplanned process interruptions may be reduced when the host system is capable of receiving digital signals.

Abstract: A method for analyzing a level gauge, comprising storing in a storage device a consecutive sequence of data triplets including a time stamp, a filling level measurement, and an echo curve information, plotting a trend line including filling level as a function of time, graphically indicating a pointer in the trend line, displaying an echo curve corresponding to a point in time initially represented by the pointer, receiving user input indicating a set of points along a section of the trend line selected for analysis, and for each point in the set of points, moving the pointer to this point and replacing contents of the second graphical element, such that an echo curve displayed in the second graphical element always corresponds to a point in time represented by a current position of the pointer. The invention enables a user to analyze operation of the level gauge during a time period corresponding to the selected trend line section.

Abstract: A method for analyzing a level gauge, comprising storing in a storage device a consecutive sequence of data triplets including a time stamp, a filling level measurement, and an echo curve information, plotting a trend line including filling level as a function of time, graphically indicating a pointer in the trend line, displaying an echo curve corresponding to a point in time initially represented by the pointer, receiving user input indicating a set of points along a section of the trend line selected for analysis, and for each point in the set of points, moving the pointer to this point and replacing contents of the second graphical element, such that an echo curve displayed in the second graphical element always corresponds to a point in time represented by a current position of the pointer. The invention enables a user to analyze operation of the level gauge during a time period corresponding to the selected trend line section.

Abstract: The present invention relates to a radar level gauge comprising a reference reflector arranged at a known reference reflector level in a tank. The radar level gauge is controllable between a filling level measuring state and a proof test state. In the proof test state, the radar level gauge is configured to determine a first verification level based on a reference reflector echo resulting from reflection of an electromagnetic transmit signal at the reference reflector; determine a second verification level based on a surface echo resulting from reflection of an electromagnetic transmit signal at the surface of the product; and provide the first verification level and the second verification level to allow determination of a proof test result based on at least the first verification level, the known reference reflector level and the second verification level.

Abstract: The present invention relates to a radar level gauge comprising a reference reflector arranged at a known reference reflector level in a tank. The radar level gauge is controllable between a filling level measuring state and a proof test state. In the proof test state, the radar level gauge is configured to determine a first verification level based on a reference reflector echo resulting from reflection of an electromagnetic transmit signal at the reference reflector; determine a second verification level based on a surface echo resulting from reflection of an electromagnetic transmit signal at the surface of the product; and provide the first verification level and the second verification level to allow determination of a proof test result based on at least the first verification level, the known reference reflector level and the second verification level.

Abstract: A method of monitoring operation of a radar level gauge system installed at a tank and arranged to determine a filling level of a product contained in the tank.

Abstract: A field device for determining a process parameter value, comprising a measurement device for determining a process parameter value; circuitry for determining the reliability of the process parameter value; and signaling circuitry for providing the process parameter value and an indication of the reliability of the process parameter value to a host system via a current loop. The signaling circuitry is configurable between a first state in which the indication of the reliability is provided as a digital signal and the process parameter value is provided as an analog DC-value, and a second state in which the indication of the reliability is provided as a predetermined analog DC-value. Hereby, the number of unplanned process interruptions may be reduced when the host system is capable of receiving digital signals.

Abstract: A method of monitoring operation of a radar level gauge system installed at a tank and arranged to determine a filling level of a product contained in the tank.

Abstract: A pulsed radar level gauge, comprising a transmitter for generating and transmitting a signal in the form of a pulse train, means for receiving pulses reflected in said tank, and to form an analogue tank signal based on these reflections, an analogue to digital converter for sampling and digitizing said tank signal and forming a digital time domain reflectometry (TDR) signal, and means for varying the output power of said transmitter during the transmission of said pulse train, in order to adjust an amplitude of said analogue tank signal to match the dynamics of said A/D-converter. A gain function applied on the receiver side is thus replaced by varying the output power on the transmitter side. This allows the signal-to-noise ratio to be improved, as the noise will not be amplified together with the signal.

Abstract: A method and a system for radar-based gauging of a filling level of a filling material is disclosed, wherein the tank has at least one interfering structure. The method comprises: transmitting at a first time moment a microwave signal towards the surface of the filling material; receiving microwave signals as reflected against the surface of the filling material and as reflected against said at least one interfering structure; calculating based on propagation times of the transmitted and reflected microwave signals at least two distances to reflective surfaces in the tank; and repeating at a second time moment the transmitting, the detecting and the calculating, wherein said first time moment is timely separated from said second time moment. Based on the several repeated measurements, the distance to the surface of the filling material is determined as the calculated distance that exhibits the greatest change between said first and second time moments.

Abstract: A pulsed radar level gauge, comprising a transmitter for generating and transmitting a signal in the form of a pulse train, means for receiving pulses reflected in said tank, and to form an analogue tank signal based on these reflections, an analogue to digital converter for sampling and digitizing said tank signal and forming a digital time domain reflectometry (TDR) signal, and means for varying the output power of said transmitter during the transmission of said pulse train, in order to adjust an amplitude of said analogue tank signal to match the dynamics of said A/D-converter. A gain function applied on the receiver side is thus replaced by varying the output power on the transmitter side. This allows the signal-to-noise ratio to be improved, as the noise will not be amplified together with the signal.

Abstract: A method and a system for radar-based gauging of a filling level of a filling material is disclosed, wherein the tank has at least one interfering structure. The method comprises: transmitting at a first time moment a microwave signal towards the surface of the filling material; receiving microwave signals as reflected against the surface of the filling material and as reflected against said at least one interfering structure; calculating based on propagation times of the transmitted and reflected microwave signals at least two distances to reflective surfaces in the tank; and repeating at a second time moment the transmitting, the detecting and the calculating, wherein said first time moment is timely separated from said second time moment. Based on the several repeated measurements, the distance to the surface of the filling material is determiend as the calculated distance that exhibits the greatest change between said first and second time moments.