Fisher Controls International LLC

Davin Scott Nicholas

Mitchell Stephen Panther

Matthew J Kemp

Kurtis K Jensen

Scott Richard Kratzer

Benjamin Koch

Tom Koch

Stephen George Seberger

Michael R Fontaine

David Lee Smid

Barry Lynn Gaarder

Gregory Robert Bulleit

Christopher C Arnold

Mitchell S Panther

Michael Anthony Conger

Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to an I/P coil of the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level. The controller may remove the fixed voltage applied to the I/P coil when the maximum current level is reached or when a threshold period of time has elapsed from the application of the fixed voltage to the I/P coil. The controller may diagnose, based on whether the digital logic line trip occurred prior to removing the fixed voltage, a failure in the I/P converter.

Open circuit diagnostic for pulsed solenoid I/P

Techniques for diagnosing failures in a digital solenoid I/P converter are provided herein. A controller of the I/P converter may apply a fixed voltage to the I/P converter, causing an armature to move from an off-position to an on-position in a properly-functioning I/P converter. The controller may receive an indication of whether a digital logic line trip has occurred, indicating that a current for the I/P coil has reached a desired maximum current level, and an elapsed time from the application of the fixed voltage. The controller may compare the amount of time elapsed from the application of the fixed voltage to an expected amount of elapsed time from the application of the fixed voltage to the I/P coil after which a digital logic line trip will occur for a properly functioning I/P coil and diagnose, based on the comparison, a failure in the I/P converter.

Diagnostic for pulsed solenoid I/P functionality

Level sensors having conductive target movement sensing are disclosed. An example level sensor includes a lever operatively coupled to a sensing member, a target operatively coupled to the lever, where the target includes a conductor, an inductive coil to generate a magnetic field and measure feedback signatures associated with the target and the magnetic field, and a processor to calculate a position of the sensing member based on the feedback signatures.

Level sensors having conductive target movement sensing

Loop-powered control of pneumatic process control devices is disclosed. A disclosed example apparatus includes an interface for use with a pneumatic process control device of a process control system. The interface includes a power input to scavenge power from a loop power control signal associated with the process control system, a sensor to determine a position of a movable control input associated with the process control device, a comparator to compare the determined position of the movable control input with a desired position of the movable control input, and an actuator to cause movement of the movable control input based on the comparison of the determined position with the desired position, where the actuator is to be powered with the scavenged power.

Loop-powered control of pneumatic process control devices

An accelerometer wireless position transducer or sensor is physically coupled to a control device in a process control system and includes an accelerometer that generates a signal based on a position of the control device or its actuator. The transducer converts the accelerometer signal into a wireless signal that includes a value indicative of the actuator position, and causes the wireless position feedback signal to be transmitted over a wireless channel to a valve controller, e.g., by using a short-range wireless protocol. The controller controls the valve based on the value included in the wireless signal. In some configurations, the feedback signal is received at a device paired with the transducer, and the paired device transmits the feedback signal to the controller. The paired device may be paired with multiple transducers and/or sensors, and may transmit various feedback signals to multiple recipient controllers and other devices.

Control device position feedback with accelerometer

Adjustment of loop-powered pneumatic process control device interfaces is disclosed. A disclosed example interface for use with a pneumatic process control device includes a power input to scavenge power from a loop power control signal associated with the process control system, a movement controller to cause movement of an actuator powered by the loop power, where the actuator is operatively coupled to a movable control input associated with the process control device, and a calibrator to read position feedback of the actuator during the movement to calculate a positional error, where the calibrator is to adjust a set point of the loop power control signal based on the positional error to control the actuator.

Adjustment of loop-powered pneumatic process control device interfaces

An apparatus includes a housing, a touch sensor, a display, and a control module. The housing has a body defining a volume to accommodate a process control device and is adapted to withstand a threshold internal pressure greater than an external pressure. The housing further has a transparent portion having first and second surfaces. The touch sensor is disposed adjacent to the second surface of the transparent portion and senses an input received within a minimum distance from the first surface of the transparent portion. The display is disposed adjacent to the touch sensor and displays at least one adjustable variable corresponding to the process control device.

Local user interface for explosion resistant field instruments using capacitive touch sensing

A diagnostic device is physically coupled to a control device in a process control system, and includes an accelerometer that determines when a motion or vibration of the control device is greater than a predetermined threshold. When this condition is detected, one or more other components of the diagnostic device (e.g., processor, communication module, etc.) are activated, and a distress signal is transmitted from the diagnostic device using the activated components. Consequently, the duty cycles of components of the diagnostic device are decreased and optimized, leading to significant power savings. Indeed, in some embodiments, energy harvesting may be sufficient to power the diagnostic device. Further, in some embodiments, the diagnostic device may not require a component processor.

Control device diagnostic using accelerometer

A continuously powered field device for use in a process control system includes a field device housing, a primary power port disposed within or connected to the field device housing, and a power source switching module comprising a first power terminal, a second power terminal, and a third power terminal. The first power terminal is coupled to the primary power port, and the third power terminal is configured to deliver power applied to the third power terminal to at least a portion of the field device. The power source switching module is operable in a first state of operation to couple the first power terminal to the third power terminal, and the power source switching module is operable in a second state of operation to couple the second power terminal to the third power terminal.

Continuously powered field device

An intrinsically safe redundant regulator circuit includes a plurality of voltage limiting regulators between a regulated rail and a ground rail. Each of the plurality of voltage limiting regulators includes: (i) a shunt regulator component configured to clamp a voltage across the regulated rail and the ground rail to a safety clamp voltage value; and (ii) one or more components, where a property of each of the one or more components is selected to configure the safety clamp voltage value.

Intrinsically safe voltage limiting shunt regulator circuit

A system and method for controlling a remote valve includes temporarily driving or activating a battery-powered pilot valve assembly to place an operatively coupled output valve assembly in a switch position. A processor energizes a bistable valve of the pilot valve assembly to enable a fluid supply to drive the output valve assembly to a desired switch position, whereupon the pilot valve assembly may be de-energized and the switch position of the output valve assembly maintained.

System and method for controlling a remote valve

An assembly configured to protect a circuit board from electromagnetic interference. The assembly includes a metal shield and an enclosure. The metal shield includes a metal plate and a plurality of tangs. The plurality of tangs are spaced about and extend transversely away from at least a portion of a perimeter portion of the metal plate. The enclosure has a bottom wall and at least one sidewall disposed around a perimeter of the bottom wall, the at least one sidewall configured to urge the tangs of the metal shield inward when the metal shield is disposed in the enclosure.

Electromagnetic interference shield

A device for protecting a circuit board from electromagnetic interference, and which includes shield to be attached to the circuit board. The device includes a metal plate and a plurality of tangs. The metal plate has a perimeter portion. The plurality of tangs are spaced about and extend transversely away from at least a portion of the perimeter portion of the metal plate. Each tang includes a bridge portion and a finger portion. The bridge portion has a first end attached to the perimeter portion and a second end spaced away from the perimeter portion and attached to the finger portion. The finger portion extends away from the second end of the bridge potion and is disposed at an obtuse angle relative to the bridge portion such that the plurality of tangs, in combination, are adapted to receive the circuit board.

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Marshalltown, IA, United States of America

Davin Scott Nicholas