Methods for detecting sensor faults in a consumer appliance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern consumer appliances with multiple sensors face challenges in detecting sensor connection failures, particularly pin-to-pin short circuits, which can be difficult to identify when identical sensors are connected to adjacent pins.
Innovation Solution
A method involving detecting preliminary and secondary conversion values at sensor input pins connected to an analog-to-digital converter, activating a pull-up resistor, and determining variations within predetermined thresholds to identify fault states and direct appliance operations accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple identical sensors are connected to adjacent pins to detect physical characteristics, then the sensing capability and redundancy are improved, but the difficulty of detecting pin-to-pin short circuit faults increases
Solution Approach 1:
The patent applies preliminary action by performing fault detection operations before normal sensor readings could be affected. The system executes preliminary conversion value detections and compares them against thresholds to identify potential short circuits before they compromise measurement accuracy. This proactive approach allows the system to establish a baseline and detect anomalies early in the operational sequence.
Solution Approach 2:
The patent introduces an intermediary fault detection mechanism that acts as a mediator between the sensor inputs and the control logic. By inserting comparison operations with predetermined thresholds and analyzing variations between parallel sensor readings, the system creates an intermediate detection layer that identifies short circuit conditions without requiring direct observation of the physical fault condition.
2Device complexity
If standard sensor connections are used without additional fault detection circuitry, then the device complexity is reduced, but the reliability of sensor readings deteriorates
Solution Approach 1:
The patent applies universality by enabling the existing sensor input pins and ADC to perform multiple functions: both normal temperature sensing and fault detection. The same hardware infrastructure is used for both measurement purposes through multi-functionality, avoiding the need for separate dedicated fault detection circuitry while maintaining reliability.
Solution Approach 2:
The system applies self-service by using its own existing resources (the sensor inputs and ADC) to perform self-diagnosis. The fault detection mechanism leverages the sensor connections themselves to detect faults, allowing the system to monitor its own health without external assistance or additional specialized components.
3Reliability
If fault detection operations are performed continuously, then the reliability of fault identification is improved, but the energy consumption increases
Solution Approach 1:
The patent applies periodic action by performing fault detection operations at specific intervals or under specific conditions rather than continuously. The system executes preliminary and secondary conversion value detections in a structured sequence, comparing variations at different stages to identify faults when necessary while allowing normal operation during intervals between detection cycles.
Solution Approach 2:
The system applies partial action by performing fault detection only to the extent necessary - using comparison with thresholds and variation analysis rather than exhaustive continuous monitoring. The detection is sufficient to identify fault conditions without the excessive energy consumption of constant full-scale monitoring, achieving adequate reliability with reduced energy expenditure.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Effectively detects and responds to sensor connection faults, including short circuits, ensuring accurate sensor readings and preventing aberrant operations in consumer appliances like water heaters.
Implementation Method 1
activating a pull-up resistor in electrical communication with the first sensor input pin
Data Source
AI summary
A method for operating a consumer appliance, as provided herein, may include detecting a preliminary first conversion value from a first sensor input pin electrically connected to an analog-to-digital converter (ADC) and detecting a preliminary second conversion value from a second sensor input pin electrically connected to the ADC in electrical parallel with the first sensor input pin. The method may further include determining a preliminary variation between the preliminary first and second conversion values is less than or equal to a predetermined preliminary threshold. The method may still further include activating a pull-up resistor in electrical communication with the first sensor input pin, identifying a fault state in response based on a conversion value variation following activating the pull-up resistor, and directing the appliance based on the determined fault state.