DEGRADING SENSOR DETECTION IMPLEMENTED WITHIN A TRANSMITTER
First Claim
1. A process variable transmitter, comprising:
- A sensor sensing a process variable and providing a sensor value indicative of the sensed process variable;
a memory storing a filtered sensor value that is calculated based on a prior received sensor value, and a filtered rate of change value that is calculated based on a prior rate of change value; and
a controller receiving the sensor value, from the sensor that senses the process variable, and comparing the sensor value to the filtered sensor value to obtain a rate of change value, the controller further comparing the rate of change value to the filtered rate of change value to obtain a deviation value, and generating an output indication based on the deviation value.
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Accused Products
Abstract
A process variable transmitter includes a memory that stores a filtered sensor value that is calculated based on a prior received sensor value and a filtered rate of change value that is calculated based on a prior rate of change value. The process variable transmitter also includes a controller that receives a sensor value and compares it to the filtered sensor value to obtain a rate of change value. The controller also compares the rate of change value to the filtered rate of change value to obtain a deviation value, and generates an output indication, such as a sensor failure warning output, based on the deviation value. This is done within the process variable transmitter.
10 Citations
20 Claims
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1. A process variable transmitter, comprising:
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A sensor sensing a process variable and providing a sensor value indicative of the sensed process variable; a memory storing a filtered sensor value that is calculated based on a prior received sensor value, and a filtered rate of change value that is calculated based on a prior rate of change value; and a controller receiving the sensor value, from the sensor that senses the process variable, and comparing the sensor value to the filtered sensor value to obtain a rate of change value, the controller further comparing the rate of change value to the filtered rate of change value to obtain a deviation value, and generating an output indication based on the deviation value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. A method of identifying characteristics of sensor signals, using a processor in a process variable transmitter, the method comprising:
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receiving, at the processor in the process variable transmitter, a sensor value from a sensor that senses a process variable; comparing, with the processor in the process variable transmitter, the sensor value to a stored sensor value stored in memory in the process variable transmitter, the stored sensor value being indicative of a plurality of prior received sensor values; identifying, with the processor in the process variable transmitter, a sensor characteristic based on the comparison, indicative of whether the sensor is operating correctly; and when the sensor is not operating correctly, generating, with the processor in the process variable transmitter, an output indication. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18)
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19. A process variable transmitter, comprising:
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a memory storing a predefined sensor relationship indicative of an expected relationship between sensor values input from a plurality of different sensors; and a processor disposed within the process control transmitter, and receiving input sensor values from the plurality of different sensors, the controller accessing the predefined sensor relationship in the memory to determine whether the input sensor values exhibit the expected relationship, and, if not, the controller generating a sensor warning output. - View Dependent Claims (20)
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Specification