Abstract: Differential density system and method. A differential pressure transmitter measures a pressure difference between first and second pressure sensing locations. A reference vessel in fluid communication with the first pressure sensing location contains a reference fluid and a sample vessel in fluid communication with the second pressure sensing location contains a sample fluid. The reference fluid is in a first column above the first pressure sensing location and the sample fluid is in a second column above the second pressure sensing location. The second column is of substantially equal height as the first column. A value of total dissolved solids (TDS) in the sample fluid is determined based on the pressure difference.

Abstract: A configuration tool is for a vortex flowmeter having a flowtube, a bluff body positioned in the flowtube for shedding vortices in the fluid, and a pressure sensor configured to obtain a signal indicative of a time-varying fluid pressure having an oscillation associated with the vortices. The configuration tool includes a processor that determines a type of fluid flowing through the flowtube based on the amplitude of the oscillation. The processor sets a fluid-type setting of the vortex meter to match the determined type of fluid. An alarming system for a control system including such a flowmeter includes a processor that assesses a density of a fluid flowing through the flowtube based on the amplitude and compares the assessed density to a fluid density configuration setting. The processor activates an alarm if the difference between the assessed density and the fluid density configuration setting exceeds a threshold.

Abstract: A configuration tool is for a vortex flowmeter having a flowtube, a bluff body positioned in the flowtube for shedding vortices in the fluid, and a pressure sensor configured to obtain a signal indicative of a time-varying fluid pressure having an oscillation associated with the vortices. The configuration tool includes a processor that determines a type of fluid flowing through the flowtube based on the amplitude of the oscillation. The processor sets a fluid-type setting of the vortex meter to match the determined type of fluid. An alarming system for a control system including such a flowmeter includes a processor that assesses a density of a fluid flowing through the flowtube based on the amplitude and compares the assessed density to a fluid density configuration setting. The processor activates an alarm if the difference between the assessed density and the fluid density configuration setting exceeds a threshold.

Abstract: A menu navigation engine that enables user configuration of a vortex flowmeter. The vortex flowmeter includes a memory device and a processor, among other hardware components. Software instructions stored on the memory device and executable by the processor implement the menu navigation engine by displaying use case identifiers on the user interface, receiving selections of use case identifiers via the user interface, generating a formatted hierarchical tree of vortex flowmeter configuration nodes associated with the selected use case, and displaying the generated tree on the user interface.

Abstract: A configuration tool is for a vortex flowmeter having a flowtube, a bluff body positioned in the flowtube for shedding vortices in the fluid, and a pressure sensor configured to obtain a signal indicative of a time-varying fluid pressure having an oscillation associated with the vortices. The configuration tool includes a processor that determines a type of fluid flowing through the flowtube based on the amplitude of the oscillation. The processor sets a fluid-type setting of the vortex meter to match the determined type of fluid. An alarming system for a control system including such a flowmeter includes a processor that assesses a density of a fluid flowing through the flowtube based on the amplitude and compares the assessed density to a fluid density configuration setting. The processor activates an alarm if the difference between the assessed density and the fluid density configuration setting exceeds a threshold.

Abstract: A menu navigation engine that enables user configuration of a vortex flowmeter. The vortex flowmeter includes a memory device and a processor, among other hardware components. Software instructions stored on the memory device and executable by the processor implement the menu navigation engine by displaying use case identifiers on the user interface, receiving selections of use case identifiers via the user interface, generating a formatted hierarchical tree of vortex flowmeter configuration nodes associated with the selected use case, and displaying the generated tree on the user interface.

Abstract: A field device for use in a process control system having embedded firmware stored in a a nonvolatile memory. The firmware includes computer-executable instructions for performing fixed behaviors and/or standard measurements as well as a runtime interpreter. The interpreter executes application specific code downloaded to the field device. When executed, the application specific code performs custom field device functions.

Abstract: A field device for use in a process control system having embedded firmware stored in a a nonvolatile memory. The firmware includes computer-executable instructions for performing fixed behaviors and/or standard measurements as well as a runtime interpreter. The interpreter executes application specific code downloaded to the field device. When executed, the application specific code performs custom field device functions.

Abstract: A menu navigation engine that enables user configuration of a vortex flowmeter. The vortex flowmeter includes a memory device and a processor, among other hardware components. Software instructions stored on the memory device and executable by the processor implement the menu navigation engine by displaying use case identifiers on the user interface, receiving selections of use case identifiers via the user interface, generating a formatted hierarchical tree of vortex flowmeter configuration nodes associated with the selected use case, and displaying the generated tree on the user interface.

Abstract: A configuration tool is for a vortex flowmeter having a flowtube, a bluff body positioned in the flowtube for shedding vortices in the fluid, and a pressure sensor configured to obtain a signal indicative of a time-varying fluid pressure having an oscillation associated with the vortices. The configuration tool includes a processor that determines a type of fluid flowing through the flowtube based on the amplitude of the oscillation. The processor sets a fluid-type setting of the vortex meter to match the determined type of fluid. An alarming system for a control system including such a flowmeter includes a processor that assesses a density of a fluid flowing through the flowtube based on the amplitude and compares the assessed density to a fluid density configuration setting. The processor activates an alarm if the difference between the assessed density and the fluid density configuration setting exceeds a threshold.

Abstract: Two-wire transmitters are described in which the required voltage that a control room must supply to the transmitter is lower at high current than at low current, thus freeing up more voltage for other uses, and in which a constant set of operating voltages may be maintained. A corrected pressure in a vortex flow meter may be determined that reflects the mass flow rate. Thus, the mass flow rate may be determined based on the corrected pressure reading and a measured volumetric flow rate. Density may be determined from pressure and temperature using a table containing error values based on a standard density determination and a relatively simple approximation. During operation of a flow meter, the stored error values may be linearly interpolated and the approximation may be computed to determine the density from the stored error value.

Abstract: Process variable transmitters, and method for calibrating such device, are disclosed that support calibrating, within a single transmitter device, multiple operating ranges such that a transmitter can switch from a first calibration correction definition associated with a first calibrated range, to a second calibration correction definition associated with a second calibrated range without having to perform a calibration procedure. Thus, rather than supporting only a single calibration definition, a calibration memory for the process variable transmitter comprises multiple calibration correction definition entries. Each calibration correction definition entry potentially expresses a correction relationship for one of multiple calibrated ranges represented in the calibration memory.

Abstract: A low power analog output circuit is disclosed that utilizes a low pass filter driven by a bit stream to render a waveshaped output signal based upon a raw digital data signal. The analog output circuit includes sequential bit pattern selection logic that receives as an input, the raw digital data signal. The analog output circuit also includes a bit pattern storage that specifies bit stream sequences that are selected in accordance with control signals generated by the state machine based upon its current state and the current raw digital data signal. The analog output circuit includes an output stage driven by a digital input signal corresponding to values provided by a bit stream sequence selected from the bit pattern storage. The output stage comprises a low pass filter circuit having an effective time constant that is greater than a hold period associated with a single bit of the bit stream sequence that drives the digital input signal.

Abstract: A method and system comprising providing a plurality of control signals, the control signals having one or more on periods that do not coincide with the on periods of the other control signals and a first frequency at which the one or more on periods are repeated, the method and system also including driving a plurality of process measurement transducers in response to the control signals by selectively coupling the transducers to ground, and capturing the output of the process measurement transducers within the one or more on periods of the control signals.

Abstract: The systems described herein include a multivariable transmitter with one or more bridge sensors for measuring absolute pressure, differential pressure, and temperature of a process fluid in a pipe. In order to reduce current draw, the sensors are excited one at a time, each during an on period of a drive signal. Each sensor output is captured by a gated integrator that is coupled to the sensor output within the on period. The gated integrator stores a value representative of the sensor output on a node that may then be sampled by an analog-to-digital converter. Using this approach, the analog-to-digital converter may sample at a frequency independent of the frequency of the sensor drive signal. For example, the analog-to-digital converter may sample at a frequency that is less than one-half the frequency of the on period, in order to avoid certain artifacts of the digitization process.