Abstract: There is disclosed a probe used with a measurement instrument including a pulse circuit for generating pulses. A coaxial connector is secured to the probe case so that the probe case is electrically connected to the ground shield. A center rod has a top end received in the probe case and to extend into a process liquid. The center rod is electrically connected to the center terminal for conducting the pulses. Ground rods are spaced around the center rod and are secured to the probe case. The probe provides an open configuration less susceptible to build-up between the center rod and the ground rods. One or more of the ground rods may by tubes, connected to a flushing port, with nozzles for cleaning the enter rod. Another ground rod may be tubular for carrying a conductor connected to a bottom of the center rod for bottom-up measurement.

Abstract: There is disclosed a radar transmitter for emulsion measurement comprising a probe defining a transmission line for sensing impedance. A first excitation circuit is connected to a top of the probe for generating downward travelling excitation signals on the transmission line and receiving a reflected signal from the transmission line. A second excitation circuit is connected to a bottom of the probe for generating upward travelling excitation signals on the transmission line and receiving a reflected signal from the transmission line, each of the reflected signals comprising a waveform of probe impedance over time. A controller is operatively connected to the excitation circuits.

Abstract: A redundant level measuring system comprises comprising a chamber for fluidic coupling to a process vessel whereby material level in the vessel equalizes with material level in the chamber. A float including a magnet in the chamber interior space rises and falls with material level in the chamber. The float comprises an inner cylindrical wall defining an elongate through opening. A magnet actuated visual indicator is mounted to the chamber for indicating level of the magnet in the chamber. A level measurement instrument includes a measurement circuit and a coaxial probe having an inner rod and a coaxial outer tube. The probe defines a transmission line and the coaxial outer tube has a through opening so that material level in the chamber equalizes with material level in the coaxial outer tube. The instrument is mounted atop the chamber with the probe directed downwardly to the chamber interior space and extending through the float through opening.

Abstract: There is disclosed a probe used with a measurement instrument including a pulse circuit for generating pulses. A coaxial connector is secured to the probe case so that the probe case is electrically connected to the ground shield, A center rod has a top end received in the probe case and to extend into a process liquid. The center rod is electrically connected to the center terminal for conducting the pulses. Ground rods are spaced around the center rod and are secured to the probe case. The probe provides an open configuration less susceptible to build-up between the center rod and the ground rods. One or more of the ground rods may by tubes, connected to a flushing port, with nozzles for cleaning the enter rod. Another ground rod may be tubular for carrying a conductor connected to a bottom of the center rod for bottom-up measurement.

Abstract: A level measurement instrument comprises an analog circuit for transmitting a pulse signal at a target of interest and receiving reflected echoes of the pulse signal and developing an echo waveform representative of the reflected echoes. A programmed digital circuit is operatively coupled to the analog circuit and comprises a programmed controller and memory. The controller is operatively programmed to identify peaks in the echo waveform and store an active peak list in the memory from a current measurement scan and a buffer peak list from prior measurement scans. The controller is further programmed to match peaks in the active peak list to peaks in the buffer peak list, to select a target peak from the active peak list based on which of the matched peaks have moved, and determining material level responsive to the target peak.

Abstract: There is disclosed herein a probe comprising a process connection for mounting to a process vessel. A sealed connector is for connection to the measurement instrument and includes an extension sleeve. A return tube extends from the extension sleeve and is secured to the process connection, the return tube has a connector end proximate the sealed connector and a distal end including vent openings below the process connection. A process tube is connected to the distal end of the return tube and extends into the process vessel. A center conductor is coaxial with the return tube and the process tube for conducting the pulses. A target tube is coaxial with and received within the return tube to define a condensation return path therebetween. The target tube extends downward from a near end at the return tube connector end by bottom end to a position below the process connection. The target tube includes apertures at the near end opening into the condensation return path.

Abstract: A through air measurement instrument comprises a housing for mounting to a process vessel and including a waveguide. A control circuit in the housing controls operation of the instrument for determining level. An RF circuit board in the housing is operatively controlled by the control circuit and includes a microwave transceiver circuit connected via a coupler to strip line traces on the printed circuit board for coupling a high frequency radar signal with the waveguide for measuring level. A multi-function RF shield comprises a cover for the RF circuit board. The cover includes a metallic covering on an inside surface for capping the waveguide and providing an RF shield.

Abstract: A loop powered process instrument comprises a control system measuring a process variable and developing a measurement signal representing the process variable. A two-wire circuit, for connection to a remote power source using a two-wire process loop, controls current on the loop in accordance with the measurement signal. A power supply with galvanic isolation is connected to the two-wire circuit and the control system to isolate the two-wire circuit from the control system. The power supply receives power from the two-wire process loop and supplies power to the control system. The power supply comprises a voltage regulator receiving loop power and developing a regulated output voltage. A current switching circuit receives the regulated output voltage and drives a primary of a transformer. A secondary of the transformer is coupled to the control system. A voltage shift control includes an isolator circuit driven by the control system for controlling voltage supplied by the voltage regulator.

Abstract: A measurement instrument comprises a housing including a measurement circuit for measuring a process variable. A primary element is adapted to extend into a process vessel. The primary element includes an elongate hollow sleeve open to an interior of the process vessel, in use. A process adapter operatively connects the housing to the primary element for securing the instrument to the process vessel. The process adapter comprises a through opening. A seal adapter is received in the process adapter through opening. The seal adapter comprises a central bore opening into the hollow sleeve. The process adapter comprises a flushing port in communication with the through opening and an annular space between the seal adapter and the process adapter intersecting the flushing port. The seal adapter comprises a plurality of jet passages aligned at the annular space and opening into the bore.

Abstract: A radar transmitter for emulsion measurement comprises a probe mountable to a bottom of a vessel and defining a transmission line extending upward into the vessel, in use, for sensing impedance. A pulse circuit is connected to the probe for periodically generating pulses on the transmission line and receiving a reflected signal from the transmission line, each reflected signal comprising a waveform of probe impedance over time. A controller is operatively connected to the pulse circuit and comprises a programmed processor and a memory. The memory stores trace data of a plurality of individual waveforms. The processor is programmed to profile a first section of the waveforms which does not change over time and a second section of the waveforms which changes over time, representing an emulsion moving in the vessel. The controller locates where the waveforms indicates motion to determine emulsion level.

Abstract: There is disclosed herein a probe comprising a process connection for mounting to a process vessel. A sealed connector is for connection to the measurement instrument and includes an extension sleeve. A return tube extends from the extension sleeve and is secured to the process connection, the return tube has a connector end proximate the sealed connector and a distal end including vent openings below the process connection. A process tube is connected to the distal end of the return tube and extends into the process vessel. A center conductor is coaxial with the return tube and the process tube for conducting the pulses. A target tube is coaxial with and received within the return tube to define a condensation return path therebetween. The target tube extends downward from a near end at the return tube connector end by bottom end to a position below the process connection. The target tube includes apertures at the near end opening into the condensation return path.

Abstract: A level measurement instrument comprises an analog circuit for transmitting a pulse signal at a target of interest and receiving reflected echoes of the pulse signal and developing an echo waveform representative of the reflected echoes. A programmed digital circuit is operatively coupled to the analog circuit and comprises a programmed controller and memory. The controller is operatively programmed to identify peaks in the echo waveform and store an active peak list in the memory from a current measurement scan and a buffer peak list from prior measurement scans. The controller is further programmed to match peaks in the active peak list to peaks in the buffer peak list, to select a target peak from the active peak list based on which of the matched peaks have moved, and determining material level responsive to the target peak.

Abstract: A loop powered process instrument comprises a control system including a control circuit, a modem circuit and a loop output circuit. The control circuit measures a process variable and develops a measurement signal representing the process variable and includes a loop control circuit and a communication circuit. The modem circuit is operatively connected to the communication circuit and includes a modulation input port and a modulation output port. The loop output circuit receives a measurement signal from the loop control circuit and is connected to the modulation input port. A two-wire circuit is for connection to a remote power source using a two-wire process loop. A power supply with isolation is connected to the two-wire circuit and the loop output circuit to isolate the two-wire circuit from the control system.

Abstract: A loop powered process instrument comprises a control system measuring a process variable and developing a measurement signal representing the process variable. An output circuit, for connection to a remote power source using a two-wire process loop, controls current on the loop in accordance with the measurement signal. A power supply is connected to the output circuit and the control system. The power supply receives power from the two wire process loop and supplies power to the control system. The power supply comprises a voltage regulator receiving loop power and developing a regulated output voltage and an adjustable shunt regulator controlling voltage supplied to the voltage regulator.

Abstract: A magnetostrictive sensing instrument comprises a probe including a tube having a near end and a distal end. A magnetostrictive wire is in the tube. An adaptor at the tube near end includes a probe circuit comprising a drive circuit for the magnetostrictive wire, a pickup sensor, a preamplifier and a memory circuit storing calibration parameters for the probe. An instrument housing includes a control circuit. A connector is operatively disposed between the instrument housing and the adaptor and comprises electrical conductors for connecting the control circuit to the probe circuit.

Abstract: A redundant level measuring system comprises a chamber for fluidic coupling to a process vessel whereby material level in the vessel equalizes with material level in the chamber. A float including a magnet in the chamber rises and falls with material level in the chamber. A magnet actuated visual indicator is mounted to the chamber for indicating level of the magnet in the chamber. A measurement instrument includes an antenna and a measurement circuit. The instrument is mounted atop the chamber with the antenna extending downwardly into the chamber. The measurement circuit measures time of flight of a through air signal representing level of the material in the chamber. A shield in the chamber isolates the float from the antenna.

Abstract: A radar transmitter for emulsion measurement comprises a probe defining a transmission line for sensing impedance. A pulse circuit is connected to the probe for generating pulses on the transmission line and receiving a reflected signal from the transmission line. The reflected signal comprises a waveform of probe impedance over time. A controller is operatively connected to the pulse circuit. The controller profiles content of the emulsion responsive to the waveform by transforming the waveform into impedance relative to distance, converting the transformed waveform into effective dielectric relative to distance, determining mixture content of the emulsion at select distances responsive to the effective dielectric at the select distances and developing an output representing mixture content relative to level units.

Abstract: A process measurement instrument comprises a process adaptor for mounting to a process vessel or the like and operatively associated with a sensing element for sensing a process variable and including plural electrical conductors. An instrument housing includes a control circuit. A connector assembly is operatively disposed between the instrument housing and the process adaptor for removably connecting the instrument housing to the process adaptor. The connector assembly comprises a first connector including a cylindrical connector body having an offset boss with a first multi-pin wire connector.

Abstract: There is disclosed herein a method of measuring and profiling a process liquid in a process vessel. The process liquid includes an emulsion layer between two media of differing dielectric constants. An electromagnetic signal is generated and transmitted along a probe, defining a transmission line, extending into the vessel. The transmission line comprises a conductor in contact with the process liquid with an insulating coating on the conductor to maximize signal penetration in the process liquid. A reflected signal is received from the transmission line and a programmed controller is operatively connected to the probe for measuring characteristics of reflected signal energy along the transmission line for profiling the emulsion layer.

Abstract: A probe for use with a measurement instrument includes a circuit connected to the probe. The probe comprises a process adaptor for mounting to a process vessel and including a through bore extending from a connector end to a process end. A tubular body is received in the process adaptor at the connector end and has an outer diameter less than an inner diameter of the process adaptor at the connector end to define a cavity therebetween. The cavity is open to the process vessel. A coupling secures the body to the process adaptor. A center conductor is coaxial with the tubular body and the process adaptor. A seal element is disposed between the tubular body and the center conductor. Process pressure in the process vessel increases compressive force between the tubular body and the seal element.