Abstract: A guided wave radar level gauge adapted for mounting on a nozzle of a tank, including an attachment collar with an opening configured to be aligned with the nozzle and to be secured by means of an annular clamping device, and a transmission line probe attached to an exterior end of a probe connector. The GWR level gauge further comprises an annular sealing gasket fitted in the collar opening, the annular sealing gasket having a central opening through which the central probe connector extends, and a distancing sleeve arranged around the exterior end of the probe connector and having a radially protruding collar portion, wherein processing circuitry is configured to detect an impedance change caused by tank content or condensate which has passed through the central opening of the sealing gasket and collected in an annular space immediately surrounding the radially protruding collar portion.

Abstract: A filling level determination system, for determining a filling level of a product in a tank, comprising a measurement unit for arrangement at a measurement position, the measurement unit including a transceiver; and an antenna arrangement coupled to the transceiver for radiating an electromagnetic transmit signal generated by the transceiver from the measurement position towards a target position on the tank wall, and for returning an electromagnetic first reflection signal resulting from reflection of the transmit signal at the target position back towards the transceiver; and processing circuitry coupled to the transceiver of the measurement unit and being configured to determine the filling level based on tank deformation data indicative of a known relation between the level of the product in the tank and deformation of the tank at the first target position, and a timing relation between the first transmit signal and the first reflection signal.

Abstract: In summary, the present invention thus relates to a method of determining a level of a product in a tank, comprising generating and transmitting an electromagnetic transmit signal; guiding the transmit signal towards and into the product; returning an electromagnetic reflection signal resulting from reflection of the transmit signal; receiving, the reflection signal; determining, based on the reflection signal and a timing relation between the reflection signal and the transmit signal, an echo signal exhibiting an echo signal strength as a function of a propagation parameter indicative of position along the probe; and determining the level of the surface of the product based on a propagation parameter value indicative of a first threshold position along the probe for which the echo signal has reached a predetermined threshold signal strength, and an offset indicative of an offset distance along the probe from the first threshold position towards the second probe end.

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: A method of determining a filling level of a product in a tank having a tank wall, the method comprising: generating and transmitting an electromagnetic first transmit signal; propagating the first transmit signal through a tank atmosphere towards a corner reflector formed by the surface of the product and the tank wall where the surface of the product meets the tank wall, the corner reflector being at a known horizontal distance from the radar level gauge system; receiving an electromagnetic first reflection signal resulting from reflection of the first transmit signal at the corner reflector; determining a measure indicative of a propagation direction of the first reflection signal; and determining the filling level based on the measure indicative of the propagation direction of the first reflection signal and the known horizontal distance between the radar level gauge system and the corner reflector.

Abstract: A guided wave radar level gauge comprising a housing providing explosion proof protection and having an intrinsically safe output, a transmission line probe connected to the IS output. The housing encloses radar level gauge circuitry which is incompatible with intrinsic safety requirements, a microwave unit connected to the IS output, an electrical barrier connected between the RLG circuitry and the microwave unit, the electrical barrier having a barrier ground potential which is independent from the grounded housing wall, and a set of blocking capacitors connected between the microwave unit and the IS output.

Abstract: A valve arrangement for a guided wave radar level gauge including a valve housing holding a movable valve element having a through-opening, the movable valve element being configured to be movable between an open position and a closed position. A probe section arranged in the through-opening of the movable valve element. Upper and lower probe sections are located on respective sides of the movable valve element. A spring-loaded connection assembly is configured to form an electrical connection between the upper and the lower probe section via the probe section in the movable valve element when the movable valve element is in an open position.

Abstract: The invention provides a method and apparatus for checking the condition of a self-oscillating vibrating fork level switch. The switch includes a test facility that operates when the switch is taken from a closed loop feedback operating mode into an open loop test mode. Amplitudes of the received test signals are subjected to comparison with predetermined thresholds to establish the health of the switch.

Abstract: A radar level gauge comprising a signal propagation device, a dielectric filling member arranged in the signal propagation device, and a sealing arrangement for preventing tank content from escaping into the outside environment, wherein the dielectric filling member comprises a main body and a sealing arrangement comprising a first sealing portion. The radar level gauge further comprises a structural reinforcement element positioned above the first sealing portion.

Abstract: A method carried out using a radar level gauge system, the tank having a tank roof supporting the radar level gauge system, a tank wall, and a tank atmosphere in a space defined by a surface of a product in the tank, the tank roof, and the tank wall, wherein the method comprises generating and transmitting an electromagnetic first transmit signal; propagating the first transmit signal through the tank atmosphere towards a corner reflector formed by the surface of the product and the tank wall where the surface of the product meets the tank wall, the corner reflector being at a known horizontal distance from the radar level gauge system; receiving an electromagnetic first reflection signal resulting from reflection of the first transmit signal at the corner reflector; and performing a filling level determination and/or a verification operation for the radar level gauge system based on a timing relation between the first transmit signal and the first reflection signal, and the known horizontal distance between

Abstract: A pulsed radar level gauge comprising a pulse generator configured to generate a transmit signal (ST) in the form of a pulse train, a propagation device connected to direct the transmit signal (ST) into a tank and return a microwave return signal (SR), a receiver, sampling circuitry configured to provide a time expanded tank signal, and processing circuitry for determining said filling level based on the time expanded tank signal. The gauge further comprises impedance increasing circuitry arranged to ensure that an input impedance of the receiver is at least 2 k? and a delay line arranged between said receiver and said propagation device, the delay line configured to introduce a delay greater than said pulse duration, such that said time expanded signal includes a transmitted pulse.

Abstract: A guided wave radar level gauge comprising an explosion proof housing with an intrinsically safe (IS) output, a resistor having a first terminal connected to the IS output and a second terminal connected to the housing ground potential, and a transmission line probe connected to the IS output. The housing encloses radar level gauge (RLG) circuitry and a microwave unit having a floating ground potential, and a set of blocking capacitors connected between the microwave unit and the IS output. The microwave unit includes a differential receiver, having a first terminal connected to the IS output via the set of blocking capacitors, and a second terminal connected to the housing ground potential via the set of blocking capacitors, a voltage between the first and second terminals forming an input signal to the differential receiver.

Abstract: Method and system for detecting a cleaning process in a radar level gauge configured to determine a fill level of a product contained in a tank, the radar level gauge comprising a transceiver configured to provide a transmit signal, ST, to be propagated towards the product by a propagating device, to receive a reflected signal, SR, resulting from a reflection of the transmit signal at a surface of the product, and to determine a fill level in the tank based on the received reflected signal, wherein the method comprises: at a measurement position above the fill level and a known distance from a reference position near a ceiling of the tank, determining a difference in signal amplitude between at least two different fill level measurements; and if the determined difference in signal amplitude exceeds a predetermined threshold value, determining that a cleaning process is ongoing in the tank.

Abstract: A point level switch for industrial interface detection is described, the switch including a microwave waveguide sensor in place of the more commonly encountered vibrating fork.

Abstract: A microwave transmission arrangement, comprising an electrically conductive hollow waveguide having a first waveguide portion, a second waveguide portion between the first waveguide portion and a first end of the hollow waveguide, and a conductive transition surface of the hollow waveguide forming a transition between the first waveguide portion and the second waveguide portion; and a microwave circuit board including a dielectric carrier, and a first conductor pattern on a first side of the dielectric carrier, the first conductor pattern including a patch for radiating or receiving microwave signals in the predefined wavelength range, and a first ground plane surrounding the patch, wherein the first ground plane of the microwave circuit board is in conductive contact with the first end of the hollow waveguide, and extends into the second waveguide portion cross-section area to define at least one conductive pocket together with the second waveguide portion and the transition surface of the hollow waveguide.

Abstract: The present invention relates a transmission line probe for use in a radar level gauge system configured to determine a filling level (L) and a density of a product contained in a container, wherein the transmission line probe comprises: at least one probe line adapted to guide an electromagnetic transmit signal (ST) towards and at least partly through the product, and to guide an electromagnetic return signal (SR) back from a surface or interface of the product; and a plurality of insulating dielectric beads arranged along the at least one probe line and configured to decrease electromagnetic signal attenuation caused by the product. The present invention also relates to a radar level gauge system comprising such a transmission line probe, and to a corresponding method.

Abstract: A radar level gauge system comprising a transceiver; a signal propagation arrangement power monitoring circuitry for determining a presently available power for operation of the radar level gauge system; and processing circuitry coupled to the transceiver and to the power monitoring circuitry, and configured to: acquire a measure indicative of the presently available power for operation of the radar level gauge system from the power monitoring circuitry; perform a set of measurement operations dependent on the presently available power for operation of the radar level gauge system, each measurement operation including controlling the transceiver to generate and transmit an electromagnetic transmit signal, to receive an electromagnetic reflection signal, and to form a measurement signal indicative of a timing relation between the transmit signal and the reflection signal; and determine the filling level based on the measurement signal formed in each of the measurement operations in the set of measurement opera

Abstract: A radar level gauge system, comprising a transceiver; an antenna for radiating an electromagnetic transmit signal from the transceiver towards a surface of the product and for returning an electromagnetic reflection signal back towards the transceiver; a feed-through connecting the transceiver and the antenna; and processing circuitry coupled to the transceiver for determining the filling level based on a relation between the transmit signal and the reflection signal, wherein the feed-through comprises a waveguide arranged between the transceiver and the antenna to receive the transmit signal from the transceiver and guide the transmit signal towards the antenna in a guiding direction, the waveguide comprising an elongated plug arranged in a hollow conductor extending in the guiding direction, wherein the plug comprises a non-conductive sleeve member and a metallic plug member, the non-conductive sleeve member being sealingly joined to a portion of the hollow conductor and to the metallic plug member.

Abstract: A radar level gauge system, comprising a transceiver; an antenna arrangement configured to transmit an electromagnetic transmit signal from the transceiver, and to return an electromagnetic reflection signal resulting from reflection of the transmit signal at a surface of the product back towards the transceiver; and processing circuitry. The antenna arrangement comprises: a dielectric antenna body having a transmit signal receiving surface to receive the transmit signal from the transceiver, a convex transmit signal emitting surface configured to direct the transmit signal towards the product following passage of the transmit signal through the dielectric antenna body, and a side surface connecting the transmit signal receiving surface and the transmit signal emitting surface; and an electrically conductive antenna housing covering at least a portion of the side surface of the dielectric antenna body.

Abstract: The invention provides a method for configuring for use a vibrating fork level switch having a dry fork frequency DFF. The method involves establishing a wet fork frequency WFF and combining this with the DFF to configure the switch for use in media of differing densities.