公开(公告)号：US6006338A

公开(公告)日：1999-12-21

申请号：US890169

申请日：1997-07-09

申请人： Randy J. Longsdorf ,  Grant B. Edwards ,  Richard L. Nelson ,  David L. Pederson

发明人： Randy J. Longsdorf ,  Grant B. Edwards ,  Richard L. Nelson ,  David L. Pederson

IPC分类号： G05B19/418 ,  G01C25/00

CPC分类号： G05B19/4185 ,  Y02P90/18

摘要： A process transmitter communications circuit has link terminals which are coupled to a process link, which supplies power to the circuit. A power source is coupled to one of the link terminals and is independent from the power supplied from the process link. Communications circuitry is coupled to the power source and link terminals, which transmits a transmitter signal over the process link, through the link terminals. A power sensing component is coupled to at least one of the link terminals and the communications circuitry and senses whether the power supplied by the process link is inadequate to transmit the transmitter signal. A power control component is coupled to the power source, the link terminals and the communications circuitry and selectively applies power from the power source to the communications circuitry for transmitting the transmitter signal when the power sensing component senses there is inadequate power supplied by the process link.

摘要翻译： 过程发射机通信电路具有耦合到处理链路的链路终端，该过程链路向电路供电。 电源耦合到链路终端中的一个，并且独立于从过程链路提供的电力。 通信电路耦合到电源和链路终端，电源和链路终端通过链​​路终端在过程链路上发送发射机信号。 功率感测组件耦合到链路终端和通信电路中的至少一个，并且感测由过程链路提供的功率是否不足以发送发射机信号。 功率控制部件耦合到电源，链路终端和通信电路，并且当功率感测部件感测到由处理链路提供的不足的功率时，从电源将功率选择性地施加到用于发送发射机信号的通信电路 。

公开(公告)号：US5410730A

公开(公告)日：1995-04-25

申请号：US157982

申请日：1993-11-23

申请人： Randy J. Longsdorf ,  David L. Pederson

发明人： Randy J. Longsdorf ,  David L. Pederson

IPC分类号： G05B19/418 ,  G11C8/00

CPC分类号： G05B19/4185 ,  G05B2219/31121 ,  G05B2219/31166 ,  G05B2219/33184 ,  G05B2219/33187 ,  G05B2219/37003 ,  Y02P90/18

摘要： An apparatus receives a query from a process controller containing a process variable address representing a storage location for a process variable in a network of field devices. A communication standard type and an unique field device address is associated with each field device. An associating section identifies a field device address and a communication standard type associated with each of a plurality of process variable addresses. An extracting section matches the stored process variable address with a process variable address in the associating section and extracts the associated field device address and the associated communication standard type from the associating section. A generating section generates a field device request containing the extracted associated field device address as a function of the extracted associated communication standard type. The field device request is conveyable over a communication line to address the storage location represented by the stored process variable address.

摘要翻译： 装置从过程控制器接收包含表示现场设备网络中的过程变量的存储位置的过程变量地址的查询。 通信标准类型和唯一的现场设备地址与每个现场设备相关联。 关联部分识别与多个过程变量地址中的每一个相关联的现场设备地址和通信标准类型。 提取部分将存储的过程变量地址与关联部分中的过程变量地址相匹配，并从关联部分提取相关联的现场设备地址和相关联的通信标准类型。 生成部分根据提取的相关联的通信标准类型生成包含提取的相关联的现场设备地址的现场设备请求。 现场设备请求可以通过通信线路传送，以寻址由存储的过程变量地址表示的存储位置。

公开(公告)号：US5187474A

公开(公告)日：1993-02-16

申请号：US188110

申请日：1988-04-28

申请人： John A. Kielb ,  Richard L. Nelson ,  David L. Pederson

发明人： John A. Kielb ,  Richard L. Nelson ,  David L. Pederson

IPC分类号： G08C19/02

CPC分类号： G08C19/02

摘要： An existing analog two-wire transmitter has a sensor module, an analog excitation circuit, and an analog detector circuit which provides an output representative of a sensed process variable, such as pressure, to a two-wire current loop. The analog detection circuit is removed and replaced with apparatus including a digital converter that digitally calculates the transmitter's output. The output is improved by calculating correction for linearity. The analog excitation circuit may also be replaced with a replacement excitation circuit. The replacement excitation circuit and the digital converter can be energized in series to control energization current. A charge pump can be coupled to the loop to balance the current in the series circuit. The digital converter can also provide electrical span and zero adjustments.

摘要翻译： 现有的模拟双线发射机具有传感器模块，模拟激励电路和模拟检测器电路，其向双线电流回路提供表示感测的过程变量（例如压力）的输出。 模拟检测电路被去除，并用包括数字计算发射器输出的数字转换器的装置代替。 通过计算线性校正来改善输出。 也可以用替换激励电路代替模拟激励电路。 替代激励电路和数字转换器可以串联通电以控制通电电流。 电荷泵可以耦合到回路以平衡串联电路中的电流。 数字转换器还可以提供电气跨度和零点调整。

公开(公告)号：US06445192B1

公开(公告)日：2002-09-03

申请号：US09542677

申请日：2000-04-04

申请人： Eric R. Lovegren ,  David L. Pederson

发明人： Eric R. Lovegren ,  David L. Pederson

IPC分类号： G01R2704

CPC分类号： G01S7/292 ,  G01F23/284

摘要： A method for detecting the presence of a twin peak pulse in a waveform, generated by a microwave level transmitter, that is used to detect levels of first and second material interfaces relating to materials contained in a tank. The waveform develops a twin peak pulse when the first and second material interfaces are in close proximity to one another. The twin peak pulse contains overlapping first and second received wave pulses reflected from the first and second material interfaces, respectively. The method determines that the waveform contains a twin peak pulse when both a first peak point relating to the first received wave pulse and a valley are detected. A microwave level transmitter having an interface detection module that is configured to use the method of the present invention to detect the existence of a twin peak pulse in a waveform.

摘要翻译： 一种用于检测由微波级发射器产生的波形中双峰脉冲的存在的方法，其用于检测与容纳在容器中的材料相关的第一和第二材料界面的水平。 当第一和第二材料界面彼此靠近时，波形产生双峰脉冲。 双峰脉冲分别包含从第一和第二材料界面反射的重叠的第一和第二接收波脉冲。 当检测到与第一接收波脉冲相关的第一峰值点和谷值时，该方法确定波形包含双峰脉冲。 一种具有接口检测模块的微波级发射机，其配置为使用本发明的方法来检测波形中双峰脉冲的存在。