Abstract: A pipe diagnostic system includes a sensor capsule, measurement circuitry and a controller. The sensor capsule is configured to be coupled to an exterior surface of a pipe and has at least one temperature sensitive element disposed therein. The measurement circuitry is coupled to the sensor capsule and is configured to measure an electrical characteristic of the at least one temperature sensitive element and provide an indication of the measurement. The controller is coupled to the measurement circuitry and is configured to obtain a transmitter reference measurement and employ a heat transfer calculation with the transmitter reference measurement and the indication to generate an estimated process fluid temperature. The controller is further configured to obtain an indication of process fluid temperature and provide a pipe diagnostic indication based on a comparison of the estimated process fluid temperature and the obtained indication of process fluid temperature.

Abstract: A process fluid temperature measurement system includes a thermowell configured to couple to a process fluid conduit and extend through a wall of the process fluid conduit. A temperature sensor assembly is disposed within the thermowell and includes a first temperature sensitive element and a second temperature sensitive element. The first temperature sensitive element is disposed within the thermowell adjacent a distal end of the thermowell. The second temperature sensitive element is spaced apart from the first temperature sensitive element along a spacer having a known thermal conductivity. Transmitter circuitry is coupled to the first and second temperature sensitive elements and is configured to perform a heat flux calculation to provide a process fluid temperature output.

Abstract: A pipe diagnostic system includes a sensor capsule, measurement circuitry and a controller. The sensor capsule is configured to be coupled to an exterior surface of a pipe and has at least one temperature sensitive element disposed therein. The measurement circuitry is coupled to the sensor capsule and is configured to measure an electrical characteristic of the at least one temperature sensitive element and provide an indication of the measurement. The controller is coupled to the measurement circuitry and is configured to obtain a transmitter reference measurement and employ a heat transfer calculation with the transmitter reference measurement and the indication to generate an estimated process fluid temperature. The controller is further configured to obtain an indication of process fluid temperature and provide a pipe diagnostic indication based on a comparison of the estimated process fluid temperature and the obtained indication of process fluid temperature.

Abstract: A pipe diagnostic system includes a sensor capsule, measurement circuitry and a controller. The sensor capsule is configured to be coupled to an exterior surface of a pipe and has at least one temperature sensitive element disposed therein. The measurement circuitry is coupled to the sensor capsule and is configured to measure an electrical characteristic of the at least one temperature sensitive element and provide an indication of the measurement. The controller is coupled to the measurement circuitry and is configured to obtain a transmitter reference measurement and employ a heat transfer calculation with the transmitter reference measurement and the indication to generate an estimated process fluid temperature. The controller is further configured to obtain an indication of process fluid temperature and provide a pipe diagnostic indication based on a comparison of the estimated process fluid temperature and the obtained indication of process fluid temperature.

Abstract: A process fluid temperature estimation system includes a mounting assembly configured to mount the process fluid temperature estimation system to an external surface of a process fluid conduit. A sensor capsule has at least one temperature sensitive element disposed therein. Measurement circuitry is coupled to the sensor capsule and configured to detect an electrical characteristic of the at least one temperature sensitive element that varies with temperature and provide sensor capsule temperature information. A controller is coupled to the measurement circuitry and is configured to obtain a reference temperature and employ a heat transfer calculation with the reference temperature, the sensor capsule temperature information and the known thermal conductivity of the process fluid conduit to generate an estimated process fluid temperature output.

Abstract: A pipe diagnostic system includes a sensor capsule, measurement circuitry and a controller. The sensor capsule is configured to be coupled to an exterior surface of a pipe and has at least one temperature sensitive element disposed therein. The measurement circuitry is coupled to the sensor capsule and is configured to measure an electrical characteristic of the at least one temperature sensitive element and provide an indication of the measurement. The controller is coupled to the measurement circuitry and is configured to obtain a transmitter reference measurement and employ a heat transfer calculation with the transmitter reference measurement and the indication to generate an estimated process fluid temperature. The controller is further configured to obtain an indication of process fluid temperature and provide a pipe diagnostic indication based on a comparison of the estimated process fluid temperature and the obtained indication of process fluid temperature.

Abstract: A process fluid temperature measurement system includes a thermowell configured to couple to a process fluid conduit and extend through a wall of the process fluid conduit. A temperature sensor assembly is disposed within the thermowell and includes a first temperature sensitive element and a second temperature sensitive element. The first temperature sensitive element is disposed within the thermowell adjacent a distal end of the thermowell. The second temperature sensitive element is spaced apart from the first temperature sensitive element along a spacer having a known thermal conductivity. Transmitter circuitry is coupled to the first and second temperature sensitive elements and is configured to perform a heat flux calculation to provide a process fluid temperature output.

Abstract: A process device includes a controller and a wireless communications module. The wireless communications module is coupled to the controller. A power generation module is provided to generate electricity for the process device. The power generator module can be disposed within the process device or it can be a separate unit coupled to the process device.

Abstract: A process variable transmitter connects a serial bus to an accessory load. A supply limiter circuit provides a first supply current limit and provides a stored energy output. A recessive driver circuit draws a drive current from the stored energy output and couples the drive current to the serial bus. The recessive driver circuit provides a drive current limit. A dominant driver circuit has a dominant state in which it conducts the drive current, and an inactive state in which the drive current is available to the accessory load.

Abstract: A process variable transmitter connects a serial bus to an accessory load. A supply limiter circuit provides a first supply current limit and provides a stored energy output. A recessive driver circuit draws a drive current from the stored energy output and couples the drive current to the serial bus. The recessive driver circuit provides a drive current limit. A dominant driver circuit has a dominant state in which it conducts the drive current, and an inactive state in which the drive current is available to the accessory load.