摘要:
A process variable transmitter for measuring a pressure of a process fluid includes a process coupling having a first port configured to couple to a first process pressure and a second port configured to couple to a second process pressure. A differential pressure sensor is coupled to the first and second ports and provides an output related to a differential pressure between the first pressure and the second pressure. First and second pressure sensors couple to the respective first and second ports and provide outputs related to the first and second pressures. Transmitter circuitry is configured to provide a transmitter output based upon the output from the differential pressure sensor and/or the first and/or second pressure sensors. Additional functionality is provided by the transmitter using the sensed first and/or second pressures.
摘要:
A process variable transmitter for measuring a pressure of a process fluid includes a process coupling having a first port configured to couple to a first process pressure and a second port configured to couple to a second process pressure. A differential pressure sensor is coupled to the first and second ports and provides an output related to a differential pressure between the first pressure and the second pressure. First and second pressure sensors couple to the respective first and second ports and provide outputs related to the first and second pressures. Transmitter circuitry is configured to provide a transmitter output based upon the output from the differential pressure sensor and/or the first and/or second pressure sensors. Additional functionality is provided by the transmitter using the sensed first and/or second pressures.
摘要:
A pressure transmitter for measuring a pressure of a process fluid in an industrial process, includes a pressure sensor having an output related to an applied pressure. Measurement circuitry coupled to the pressure sensor is configured to provide a transmitter output related to sensed pressure. A pressure coupling face having an opening therein is arranged to transfer the applied pressure to the pressure sensor. A pressure coupling flange having a flange face abutting the pressure coupling face is configured to convey the process fluid to the opening of the pressure coupling face. Features are provided to control distribution of a leading force across the pressure coupling face and the flange face.
摘要:
A pressure transmitter for measuring a pressure of a process fluid in an industrial process, includes a pressure sensor having an output related to an applied pressure. Measurement circuitry coupled to the pressure sensor is configured to provide a transmitter output related to sensed pressure. A pressure coupling face having an opening therein is arranged to transfer the applied pressure to the pressure sensor. A pressure coupling flange having a flange face abutting the pressure coupling face is configured to convey the process fluid to the opening of the pressure coupling face. Features are provided to control distribution of a leading force across the pressure coupling face and the flange face.
摘要:
A pressure sensor for sensing a pressure of a process fluid includes a sensor body exposed to the pressure of the process fluid. The sensor body deforms in response to the pressure. A diaphragm suspended from the sensor body has a tension which changes in response to deformation of the sensor body. A resonate frequency of the diaphragm is measured. The measured resonant frequency is indicative of the line pressure of the process fluid and integrity of the isolation fill fluid system. In addition to measuring the resonant frequency, the oscillation mode itself can be used as a diagnostic tool to assess sensor health.
摘要:
A process device has a process seal for coupling to an industrial process. The process device includes a process device body having an isolation cavity and an isolation passageway extending from the isolation cavity to a pressure sensor. The isolation cavity and isolation passageway filled with an isolation fluid. An isolation diaphragm is positioned to isolate the isolation cavity from process fluid. The isolation diaphragm has a process fluid side and an isolation fluid side. A weld ring is positioned around a periphery of the process fluid side of the isolation diaphragm. The weld ring is formed of a first material compatible with the isolation diaphragm and a second material compatible with the process device body. A weld secures the weld ring to the process device body.
摘要:
A process fluid flow measurement device includes a fluid flow member having an inlet with a first diameter and a throat with a second diameter that is smaller than the first diameter. A first process fluid pressure tap is disposed proximate the inlet and a second process fluid pressure tap is disposed proximate the throat. A differential pressure sensor is operably coupled to the first and second process fluid pressure taps. Differential pressure measurement circuitry is coupled to the differential pressure sensor to provide a differential pressure signal related to a difference in pressure between process fluid pressure at the first and second taps. A process fluid velocity measurement device is positioned in the throat to measure a velocity of process fluid flowing therethrough and provide a fluid velocity indication. The differential pressure sensor signal and the fluid velocity indication are used to provide a calculated indication of fluid flow. This calculated indication can be relative to multiphasic fluids such as two-phase or three-phase fluids.
摘要:
A transmitter for use in an industrial process control system, includes a process coupling configured to couple to a process fluid. A sensor housing has a cavity formed therein which is in fluidic communication with the process fluid. A diaphragm in the cavity isolates a portion of the cavity from the process fluid and moves in response to pressure applied by the process fluid. A first electrode in the isolated portion of the cavity is configured to form a first capacitance with the diaphragm and a second electrode in the isolated portion of the cavity configured to form a second capacitance with the diaphragm. Measurement circuitry coupled to the first and second capacitance measures a pressure of the process fluid based upon at least one of the first capacitance and second capacitance. The measurement circuitry further configured to measure vibrations in the process fluid based upon at least one of the first capacitance and second capacitance.
摘要:
A process device has a process seal for coupling to an industrial process. The process device includes a process device body having an isolation cavity and an isolation passageway extending from the isolation cavity to a pressure sensor. The isolation cavity and isolation passageway filled with an isolation fluid. An isolation diaphragm is positioned to isolate the isolation cavity from process fluid. The isolation diaphragm has a process fluid side and an isolation fluid side. A weld ring is positioned around a periphery of the process fluid side of the isolation diaphragm. The weld ring is formed of a first material compatible with the isolation diaphragm and a second material compatible with the process device body. A weld secures the weld ring to the process device body.
摘要:
A diagnostic system for a pressure sensor having a cavity configured to receive on applied pressure is provided. The cavity has a first and a second wall. A deflectable diaphragm is positioned in the cavity and configured to form a first and a second capacitance with the first wall and a third and a fourth capacitance with the second wall which change in response to the applied pressure. The capacitances form a first transfer function and a second transfer function. Changes in the first transfer function relative to the second transfer function are detected to provide a diagnostic output.