Abstract: 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.

Abstract: A process fluid pressure transmitter includes a process fluid pressure sensor, measurement circuitry, a controller and a loop communicator. The pressure sensor is coupleable to a source of process fluid pressure. Measurement circuitry is coupled to the process fluid pressure sensor and provides a signal indicative of the electrical characteristic of the process fluid pressure sensor. The controller receives the signal from the measurement circuitry and calculates a process fluid pressure based at least in part upon the signal. The controller is also configured to detect a process fluid pressure transient and store at least one parameter related to the process fluid pressure transient. The loop communicator is coupled to the controller and is configured to provide a signal over a process communication loop based upon the process fluid pressure. The process fluid pressure transmitter is also configured to provide an indication related to the at least one stored parameter.

Abstract: 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.

Abstract: A process fluid pressure transmitter includes a process fluid pressure sensor, measurement circuitry, a controller and a loop communicator. The process fluid pressure sensor has an electrical characteristic that varies with process fluid pressure. The pressure sensor is coupleable to a source of process fluid pressure. The measurement circuitry is coupled to the process fluid pressure sensor and provides a signal indicative of the electrical characteristic of the process fluid pressure sensor. The controller is coupled to the measurement circuitry and receives the signal and calculates a process fluid pressure based at least in part upon the signal. The controller is also configured to detect a process fluid pressure transient and store at least one parameter related to the process fluid pressure transient. The loop communicator is coupled to the controller and is configured to provide a signal over a process communication loop based upon the process fluid pressure.