Transmitter with electrical circuitry for inhibiting discharge of stored
energy
    6.
    发明授权
    Transmitter with electrical circuitry for inhibiting discharge of stored energy 失效
    具有用于抑制储存能量放电的电路的变送器

    公开(公告)号:US5585777A

    公开(公告)日:1996-12-17

    申请号:US255237

    申请日:1994-06-07

    CPC分类号: G01D3/08

    摘要: A transmitter coupled to a control loop which carries a loop current senses a process variable which is transmitted over the loop. Circuitry in the transmitter presents an effective capacitance C.sub.eff to the control loop. The transmitter includes an isolation network coupled between the circuitry and the control loop which prevents discharge of energy stored in capacitance C.sub.eff into the control loop.

    摘要翻译: 耦合到带有环路电流的控制回路的发射器感测通过回路传输的过程变量。 发射器中的电路向控制回路呈现有效电容Ceff。 发射机包括耦合在电路和控制回路之间的隔离网络,其防止存储在电容Ceff中的能量放电到控制回路中。

    Method of selecting data communication provider in a field device
    7.
    发明授权
    Method of selecting data communication provider in a field device 有权
    在现场设备中选择数据通信提供商的方法

    公开(公告)号:US07869805B2

    公开(公告)日:2011-01-11

    申请号:US11441539

    申请日:2006-05-26

    IPC分类号: H04Q7/20

    摘要: A method and apparatus are provided for allowing a field device to select a data communication provider among a plurality of available data communication providers. Preferably, the method includes periodically, or selectively, assessing the strengths and efficacy of data communication on one or more alternate data communication providers. The data communication provider with the strongest signal and/or most effective data communication is selected for use by the field device. Preferably, the field device logs events where it switches among data communication providers.

    摘要翻译: 提供了一种用于允许现场设备在多个可用数据通信提供商中选择数据通信提供商的方法和装置。 优选地,该方法包括周期性地或选择性地评估数据通信在一个或多个替代数据通信提供者上的优点和功效。 具有最强信号和/或最有效数据通信的数据通信提供商被选择供现场设备使用。 优选地,现场设备记录在数据通信提供者之间切换的事件。