Rosemount Inc.

Micromotion Gmbh

Bruce David Rovner

Scot Ronald Foss

Jared James Dreier

Steven Bruce Rogers

Kirk Allan Hunter

Jordan Dennis Lucht

Michael Jeffrey Mikolichek

Michael John Mayer

Thomas P Coursolle

Samuel Ethan Messenger

Erik D Anderson

Chad T Weigelt

Nicholas W Bond

John C Beyl

Tim Scott Lemke

A magnetic flowmeter includes a flowtube with electrodes and field coil and a transmitter that automatically determines an operating setpoint for the magnetic flowmeter based upon sensed coil inductance, sensed coil resistance, a power rating for the transmitter, the flowtube, or both, and selected performance criteria.

Magnetic flowmeter with automatic operating setpoint selection

A polymeric flow tube assembly is provided. The flow tube assembly includes a flow conduit configured to allow fluid flow therethrough. A first coil is mounted with respect to the flow conduit and disposed about a first magnetic pole member. A second coil is mounted with respect to the flow conduit and is disposed about a second magnetic pole member. The second magnetic pole member is configured to cooperate with the first magnetic pole member to generate an electromagnetic field across a flow measurement aperture. First and second electrodes are positioned within the flow tube assembly to measure an electromotive force generated within a fluid in the flow measurement aperture. At least one of the first magnetic pole member, second magnetic pole member, first electrode and second electrode is formed, at least in part, of a polymer.

Polymeric magnetic flowmeter flow body assembly

A magnetic flowmeter for measuring flow of a process fluid in a pipe includes a magnetic coil disposed adjacent to the pipe configured to apply a magnetic field to the process fluid. First and second electrodes are disposed within the pipe and electrically coupled to the process fluid and configured to sense an electromotive force (EMF) induced in the process fluid due to the applied magnetic field and flow of the process fluid. Input circuitry is coupled to the first and second electrodes and provides an output related to the sensed EMF. Diagnostic circuitry coupled to the input circuitry is configured to identify a saturation related condition and responsively provide a diagnostic output. In another embodiment, saturation prevention circuitry prevents saturation of the input circuitry.

Magnetic flowmeter with saturation prevention of the measurement circuitry

A magnetic flowmeter comprises a pipe section for process flow, a coil for generating a magnetic field across the pipe section, a current source for energizing the coil to generate the magnetic field at a coil drive frequency, and electrodes for sensing voltage induced across the process flow by the magnetic field. A processor calculates a function of the sensed voltage and generates a flow output based on the function. The processor adjusts an operating parameter of the flowmeter, such as electrode voltage sampling period, the coil drive frequency, or a phase shift, as a function of a sensed electrode-to-electrode or electrode-to-ground complex impedance.

Magnetic flowmeter with automatic adjustment based on sensed complex impedance

A flowtube assembly for a magnetic flowmeter is provided. The flowtube assembly includes a flowtube configured to receive a flow of process fluid. A magnetic core is mounted relative to the flowtube and includes a plurality of layers of a magnetically permeable material. Each layer is substantially planar and is electrically insulated from others of the plurality of layers. A coil is disposed to generate a magnetic field having field lines that are substantially orthogonal to the plane of each layer.

Magnetic core configuration for magnetic flowmeters having a plurality of layers of magnetically permeable material

A flowtube assembly for a magnetic flowmeter is provided. The flowtube assembly includes a tube extending from a first mounting flange to a second mounting flange. Each of the first and second mounting flanges has a pipe flange facing surface for mounting to a respective pipe flange. A coil chamber is disposed outside the tube, between the first and second mounting flanges. The coil chamber has at least one coil located inside that is configured to generate a magnetic field within the tube. A liner/electrode module is positioned within the tube and has a non-conductive liner, at least one electrode and at least one electrode conductor. The non-conductive liner extends from the first mounting flange to the second mounting flange. The at least one electrode is positioned in the non-conductive liner to interact with a conductive process fluid. The electrode conductor extends from the at least one electrode to an interconnect tab disposed adjacent the pipe facing flange surface of one of the first and second mounting flanges. The liner/electrode module is positionable within the tube.

Magnetic flowmeter flowtube assembly with interchangeable liner/electrode module

Magnetic flowmeter with saturation detection of the measurement circuitry

An industrial process variable transmitter includes a process variable sensor configured to sense a process variable. Measurement circuitry is coupled to the process variable sensor and provides a measured output as a function of the process variable. Output circuitry includes a loop connection configured to couple to a process control loop. An optical sensor receives the measured output from the measurement circuitry. A switching device applies pulses to the process control loop in response to an output from the optical sensor. Power supply circuitry powers the optical sensor, a comparator, and/or the switching device with power received from the process control loop and loop connection.

Industrial process variable transmitter with isolated power scavenging intrinsically safe pulse output circuitry

An apparatus comprises a pipe section for process flow, a coil for generating a magnetic field across the pipe section, a current source for energizing the coil to generate the magnetic field, and an electrode for sensing an electromotive force induced across the process flow by the magnetic field. The current source energizes the coil at a plurality of different pulse frequencies. A processor calculates a function of the electromotive force at the plurality of different pulse frequencies, and generates a flow output based on the function.

Variable frequency magnetic flowmeter

An industrial process control field device includes a process variable transducer configured to sense or control a process variable. Field device circuitry is configured to couple to the process variable transducer and communicate information related to the process variable to another location. The field device circuitry includes an optical isolator having transmit circuitry on a first side of a galvanic isolation configured to transmit an optical signal which is pulsed on and off across the isolation. Receive circuitry is located on a second side of galvanic isolation and configured to receive the optical signal with an optical sensor. The optical sensor enters an 'on' state when it receives a pulse and is otherwise in an 'off' state. The receive circuitry provides a secondary side output based upon the received optical signal. The receive circuitry enters in a low power state when the optical sensor is in the &#x201c;off&#x201d; state.

Industrial process field device with low power optical isolator

A process variable transmitter includes a sensor drive controller that outputs a sensor drive signal that is used to drive a sensor that senses a process variable. The sensor drive controller changes the frequency of the sensor drive signal to avoid frequencies and associated harmonics at which noise occurs and which could interfere with the sensor signal.

Noise detection and avoidance

An electromagnetic fluid flowmeter includes empty pipe detection circuitry. The empty pipe detection circuitry applies a common mode asynchronous signal into a pair of electrodes in the flowmeter. Impedance of fluid is determined by measuring the magnitude of the asynchronous signal between an electrode and electrical ground. Impedance is used to determine an empty pipe condition.

Magnetic flowmeter with empty pipe detector

A process control instrument receives a DC current from a two wire loop and has overcurrent protection and reverse current protection circuits which pass a portion of the DC current as a device current to a process controlling device. The overcurrent protection circuit includes a current sensing circuit which conducts the device current and generates an output indicative of device current. The overcurrent protection circuit also includes a current diverting circuit coupled across the two wire loop and responsive to the sensor output for diverting loop current in excess of a predetermined upper limit of device current back to the loop when the sensor output indicates the upper limit is reached. The reverse current protection circuit is coupled across the loop and includes a variable impedance which conducts the device current. The variable impedance inhibits the device current from flowing through the device when a loop potential is reversed from a predetermined polarity. Thus, the device current is limited to a current range controlled by the variable impedance and the upper limit.

Process control instrument with loop overcurrent circuit

A current-to-pressure converter sets line pressure to a desired pressure indicated by the current. A circuit senses the line pressure and the current, receives compensation, and outputs a compensated difference between line and desired pressures. A first driver circuit provides actuator drive based on the compensated output. The actuator controls the line pressure, but presents a temperature sensitive, reactive load to the actuator drive. A simulated load simulates a resistive part of the actuator load. A second driver provides simulated drive to the simulated load. The second driver generates the compensation which simulates actuator drive parameters, but is isolated from reactive effects and temperature sensitivity of the actuator.

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Minneapolis, MN, United States of America

Bruce David Rovner