公开(公告)号：US08290721B2

公开(公告)日：2012-10-16

申请号：US11503878

申请日：2006-08-14

申请人： David L. Wehrs ,  Evren Eryurek

发明人： David L. Wehrs ,  Evren Eryurek

IPC分类号： G01F1/00 ,  G06F19/00

CPC分类号： G01F25/0007 ,  G01F15/00

摘要： A flow meter for measuring flow of a process fluid includes a sensor configured to provide a sensor output signal. The sensor output signal is related to flow of the process fluid. Circuitry in the flow meter is configured to determine a statistical parameter related to sensor output signal. Diagnostic circuitry provides a diagnostic output based upon the determined statistical parameter and the sensor output signal.

摘要翻译： 用于测量过程流体的流量的流量计包括被配置为提供传感器输出信号的传感器。 传感器输出信号与过程流体的流量有关。 流量计中的电路配置为确定与传感器输出信号相关的统计参数。 诊断电路根据确定的统计参数和传感器输出信号提供诊断输出。

公开(公告)号：US07521944B2

公开(公告)日：2009-04-21

申请号：US11648198

申请日：2006-12-28

申请人： David L. Wehrs

发明人： David L. Wehrs

IPC分类号： G01R27/08 ,  G01F23/00

CPC分类号： G01M3/16 ,  G01M3/40 ,  H05K7/1462

摘要： A field device detects the presence of fluid in the terminal block area of the field device by generating an alternating current (AC) test current signal and measuring the amplitude of the resulting AC voltage signal. The field device includes a first terminal and a second terminal adapted for connection to a control room through a twisted-wire pair current loop. Impedance of the current loop is increased by the presence of fluid between the first terminal and the second terminal. By providing an AC test current signal to the control loop and measuring a resulting AC voltage magnitude, the impedance of the control loop can be determined. Increased impedance in the control loop indicates the presence of water in the terminal block.

摘要翻译： 现场设备通过产生交流（AC）测试电流信号并测量所得到的AC电压信号的幅度来检测现场设备的端子块区域中的流体的存在。 现场设备包括第一终端和适于通过双绞线对电流环路连接到控制室的第二终端。 通过在第一端子和第二端子之间存在流体来增加电流回路的阻抗。 通过向控制回路提供AC测试电流信号并测量所得到的AC电压幅度，可以确定控制回路的阻抗。 控制回路中增加的阻抗表示端子块中存在水。

公开(公告)号：US20080156090A1

公开(公告)日：2008-07-03

申请号：US11648198

申请日：2006-12-28

申请人： David L. Wehrs

发明人： David L. Wehrs

IPC分类号： G01F23/00

CPC分类号： G01M3/16 ,  G01M3/40 ,  H05K7/1462

摘要： A field device detects the presence of fluid in the terminal block area of the field device by generating an alternating current (AC) test current signal and measuring the amplitude of the resulting AC voltage signal. The field device includes a first terminal and a second terminal adapted for connection to a control room through a twisted-wire pair current loop. Impedance of the current loop is increased by the presence of fluid between the first terminal and the second terminal. By providing an AC test current signal to the control loop and measuring a resulting AC voltage magnitude, the impedance of the control loop can be determined. Increased impedance in the control loop indicates the presence of water in the terminal block.

摘要翻译： 现场设备通过产生交流（AC）测试电流信号并测量所得到的AC电压信号的幅度来检测现场设备的端子块区域中的流体的存在。 现场设备包括第一终端和适于通过双绞线对电流环路连接到控制室的第二终端。 通过在第一端子和第二端子之间存在流体来增加电流回路的阻抗。 通过向控制回路提供AC测试电流信号并测量所得到的AC电压幅度，可以确定控制回路的阻抗。 控制回路中增加的阻抗表示端子块中存在水。

公开(公告)号：US07659828B2

公开(公告)日：2010-02-09

申请号：US11507356

申请日：2006-08-21

申请人： David L. Wehrs ,  Robert J. Karschnia ,  Evren Eryurek

发明人： David L. Wehrs ,  Robert J. Karschnia ,  Evren Eryurek

IPC分类号： G08B21/00

CPC分类号： G01N33/2823 ,  G01F1/666 ,  G01F1/74 ,  G01N29/046 ,  G01N2291/02836 ,  G01P13/0006 ,  G01V1/28

摘要： An industrial field device provides information indicative of a process variable. The field device includes a controller, communication circuitry, a process variable sensor and measurement circuitry. The communication circuitry is coupled to the controller. The process variable sensor has an electrical characteristic that changes based on a variable of a process fluid. The measurement circuitry is coupled to the process variable sensor and coupled to the controller. The controller is configured to generate communication via the communication circuitry relative to the process variable, and to provide an indication of sand flow or other solids in the fluid.

摘要翻译： 工业现场设备提供指示过程变量的信息。 现场设备包括控制器，通信电路，过程变量传感器和测量电路。 通信电路耦合到控制器。 过程变量传感器具有基于过程流体的变量而变化的电特性。 测量电路耦合到过程变量传感器并耦合到控制器。 控制器被配置为经由通信电路相对于过程变量产生通信，并且提供流体中的沙流或其他固体的指示。

公开(公告)号：US4598251A

公开(公告)日：1986-07-01

申请号：US645835

申请日：1984-08-31

申请人： David L. Wehrs

发明人： David L. Wehrs

IPC分类号： G01R23/06 ,  H03K9/06 ,  H03K5/00 ,  H03L7/00

CPC分类号： G01R23/06 ,  H03K9/06

摘要： A circuit (10) receives a cyclic input signal having a frequency determined by a source (11), which frequency may vary in accordance with a parameter or condition to be measured, for example. The circuit (10) very precisely provides an output current representative of the frequency of the input signal. In particular, the circuit uses a pair of regulated and different voltage (16)(17), one (16) of which is impressed upon an averaging circuit (30) for a preselected time during each cycle of the input signal, and the other voltage (17) is impressed upon the averaging circuit (30) during the time when the first signal is not connected to the averaging circuit. A control signal (V.sub.o) is developed from the averaging circuit (30) which is a function of the average of the voltage provided to the averaging circuit, and the control signal (V.sub.o) in turn is used for controlling a current control amplifier (60) and transistors (61)(62) which in turn control current flow through a load (40) connected to output terminals (36)(37) and through a feedback resistor (63). The use of regulated voltage sources (16)(17) for deriving the current control signal insures great stability, relatively low cost, and precise operation.

摘要翻译： 电路（10）接收具有由源（11）确定的频率的循环输入信号，该频率可以根据例如待测量的参数或条件而变化。 电路（10）非常精确地提供表示输入信号频率的输出电流。 特别地，该电路使用一对调节和不同的电压（16）（17），其中一个（16）在输入信号的每个周期期间被预先选定的时间施加在平均电路（30）上，而另一个 在第一信号未连接到平均电路的时间期间，电平（17）施加在平均电路（30）上。 从作为提供给平均电路的电压的平均值的函数的平均电路（30）产生控制信号（Vo），控制信号（Vo）又用于控制电流控制放大器 ）和晶体管（61）（62），其又控制电流流过连接到输出端子（36）（37）的负载（40）并通过反馈电阻器（63）。 使用用于导出电流控制信号的稳压电源（16）（17）可确保极大的稳定性，相对较低的成本和精确的操作。

公开(公告)号：US09182256B2

公开(公告)日：2015-11-10

申请号：US12832341

申请日：2010-07-08

申请人： David L. Wehrs ,  Gregory J. LeCuyer ,  Jessica Lo ,  Steven J. McCoy ,  Brian L. Westfield

发明人： David L. Wehrs ,  Gregory J. LeCuyer ,  Jessica Lo ,  Steven J. McCoy ,  Brian L. Westfield

IPC分类号： G01R11/17 ,  G01R11/16 ,  G06F3/00 ,  G06F3/01 ,  G01D21/00 ,  G05B19/042

CPC分类号： G01D21/00 ,  G05B19/0423 ,  G05B2219/24069

摘要： A two-wire process variable transmitter for use in an industrial process, including a process variable sensor configured to sense a process variable of a fluid of the industrial process. Output circuitry is configured to provide an output on a two-wire process control loop which is related to the sensed process variable. Loop current measurement circuitry measures a loop current flowing through the two-wire process control loop and terminal voltage measurement circuitry measures a voltage related to a terminal voltage of the process variable transmitter. The terminal voltage can be a voltage measured across an electrical connection of the two-wire process variable transmitter to the two-wire process control loop. Input circuitry is configured to receive a diagnostic command from the two-wire process control loop. A microprocessor configured to perform loop diagnostics on the two-wire process control loop based upon the measured loop current and terminal voltage in response to receipt of a diagnostic command from the two-wire process control loop.

摘要翻译： 一种用于工业过程的二线过程变量变送器，包括被配置为感测工业过程流体的过程变量的过程变量传感器。 输出电路被配置为在与所感测的过程变量相关的二线过程控制回路上提供输出。 回路电流测量电路测量流过两线制过程控制回路的回路电流，并且端子电压测量电路测量与过程变量变送器的端子电压相关的电压。 端子电压可以是两线制过程变量发射机与两线制过程控制回路的电气连接测量的电压。 输入电路配置为从两线制过程控制回路接收诊断命令。 该微处理器被配置为响应于从两线制过程控制回路接收到诊断命令，基于所测量的回路电流和端子电压在两线制过程控制回路上执行循环诊断。

公开(公告)号：US07458280B2

公开(公告)日：2008-12-02

申请号：US11654893

申请日：2007-01-18

申请人： David L. Wehrs ,  Russell N. Evans ,  Ghidewon Arefe

发明人： David L. Wehrs ,  Russell N. Evans ,  Ghidewon Arefe

IPC分类号： G01F1/34

CPC分类号： G01F1/74 ,  G01F1/34 ,  G01F1/36 ,  G01F15/08

摘要： A process pressure fluid transmitter is coupled to a differential pressure producer and measures a differential pressure across the producer. A statistical parameter is calculated upon successive differential pressure indications, and the calculated parameter is used to indicate wet gas flow. The indication can be generated locally at the process pressure transmitter, communicated via a wired process communication loop, communicated wirelessly, or any combination thereof.

摘要翻译： 过程压力流体变送器耦合到差压生产者并测量整个生产者的差压。 统计参数是在连续差压指示下进行计算的，计算参数用于表示湿气流量。 该指示可以在过程压力变送器处本地产生，经由有线过程通信环路，无线通信或其任何组合进行通信。

公开(公告)号：US06615149B1

公开(公告)日：2003-09-02

申请号：US09576450

申请日：2000-05-23

申请人： David L. Wehrs

发明人： David L. Wehrs

IPC分类号： G01R2318

CPC分类号： G01D3/032 ,  G01D3/0365 ,  G01F1/58 ,  G01F1/60 ,  G01F25/0007

摘要： A magnetic flow transmitter provides a coil driver output at a selected fundamental to a coil on a flow tube carrying a flow of a liquid. An amplifier amplifies an electrode signal from the flow tube and an A/D converter converts the amplified electrode signal. A digital signal processor (DSP) uses a spectral transform such as a Fourier type transform to generate a flow output based on spectral components at or near the fundamental and a noise diagnosing output based on components at or near a noise frequency.

摘要翻译： 磁流量变送器将线圈驱动器输出到选定的基准线上，并在流动管上承载液体流。 放大器放大来自流管的电极信号，A / D转换器转换放大的电极信号。 数字信号处理器（DSP）使用诸如傅立叶型变换之类的频谱变换来产生基于基波处或附近的频谱分量的流量输出，以及基于噪声频率处或附近的分量的噪声诊断输出。

公开(公告)号：US06594613B1

公开(公告)日：2003-07-15

申请号：US09209134

申请日：1998-12-10

申请人： Kevin Ley ,  David C. Bohn ,  David L. Wehrs

发明人： Kevin Ley ,  David C. Bohn ,  David L. Wehrs

IPC分类号： H04B1500

CPC分类号： G01D3/032 ,  G01D3/0365 ,  G01F1/58 ,  G01F25/0007

摘要： A process variable transmitter providing a transmitter output representing a process variable sensed by a sensor. The transmitter has a filter with a bandwidth which is automatically adjusted based on noise detected in a sensor output. When the transmitter senses higher sensor noise levels, it automatically decreases the bandwidth to damp noise in the transmitter output. When the transmitter senses lower sensor noise levels, it automatically increases the bandwidth to provide faster response to changes in the process variable.

摘要翻译： 提供表示由传感器感测的过程变量的发射器输出的过程变量发射器。 发射机具有带宽的滤波器，该滤波器根据传感器输出中检测到的噪声自动调整。 当发射机感测到更高的传感器噪声电平时，它会自动降低带宽以抑制发射机输出中的噪声。 当发射机感测较低的传感器噪声电平时，它会自动增加带宽，以便对过程变量的变化提供更快的响应。

公开(公告)号：US5079957A

公开(公告)日：1992-01-14

申请号：US409935

申请日：1989-09-20

申请人： David L. Wehrs

发明人： David L. Wehrs

IPC分类号： G01F1/60

CPC分类号： G01F1/60

摘要： A magnetic flowmeter generates an alternating potential representing flow. A controlled current excites the flowmeter with first and second amplitudes of current. A correction output represents the first and second amplitudes. A circuit connected to the correction output and the alternating potential oscillates at a frequency representing the alternating potential corrected for variation of the first and second amplitudes. Frequencies of the oscillations at first and second amplitudes are measured. An output is calculated as a function of a subtraction of the first and second measured frequencies such that the effect of offset is reduced.

摘要翻译： 磁流量计产生代表流量的交替电位。 受控电流以第一和第二电流幅度激发流量计。 校正输出表示第一和第二幅度。 连接到校正输出和交替电位的电路以表示针对第一和第二幅度的变化而被校正的交变电位的频率振荡。 测量第一和第二幅度振荡的频率。 作为第一和第二测量频率的减法的函数计算输出，使得偏移的影响减小。