Field Device Drift Detection via Statistical Control Limits

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Detecting out-of-calibration field devices in industrial process facilities is challenging, especially when they are in operation, as it is difficult to identify inaccurate measurement values in real-time.

Innovation Solution

A method and system utilizing an asset management computer connected to field devices, which implements a Field Device Drift Identifying (FDDI) program to statistically determine process control limits from historical data, continuously sample current data, and compare it to these limits to detect drifts, generating alerts for necessary calibrations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If field devices are calibrated according to fixed scheduled maintenance intervals, then equipment reliability is maintained, but maintenance time and resources are wasted on devices that do not need calibration

Engineering Contradiction:
Improveequipment reliabilityVSAvoidmaintenance time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system transitions from static fixed-interval calibration scheduling to dynamic condition-based calibration scheduling. It continuously monitors field device parameter data and automatically adjusts calibration timing based on actual device performance and drift detection, ensuring calibration is performed only when necessary rather than following rigid predetermined schedules

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system implements continuous feedback loops by monitoring field device parameter data in real-time, comparing current readings against historical baselines and control limits, and generating calibration alerts when drift is detected. This feedback mechanism enables proactive calibration scheduling based on actual device condition rather than reactive calendar-based scheduling

Inventive Principle:
Principle #23Feedback

2Measurement precision

If field devices are monitored continuously to detect calibration drift, then measurement precision is improved, but device complexity and monitoring system complexity increase

Engineering Contradiction:
Improvemeasurement precisionVSAvoidmonitoring system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The monitoring system performs self-service through automated statistical analysis and drift detection algorithms. It automatically collects field device parameter data, establishes baseline control limits from historical data, continuously compares current readings against these limits, and generates calibration alerts without requiring complex manual intervention or sophisticated external monitoring infrastructure

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system monitors changes in parameter values and their statistical distribution over time. By tracking parameter drift through statistical control limits and standard deviations, it detects calibration degradation without requiring complex physical measurements or additional sensors, simply analyzing existing parameter data trends

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If calibration is performed on all field devices regardless of actual need, then measurement accuracy is ensured, but loss of substance and resource waste increase

Engineering Contradiction:
Improvemeasurement accuracyVSAvoidresource waste
Core Design Contradiction:
Measurement precisionVSLoss of substance

Solution Approach 1:

The system performs preliminary drift detection and assessment before calibration is actually performed. By continuously monitoring parameter data and detecting drift trends in advance, it identifies which devices require calibration ahead of time, enabling targeted calibration scheduling that prevents both over-calibration and under-calibration of field devices

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentUS9625892B2System and method for monitoring device calibration
Publication Date: 2017.04.18 HONEYWELL INTERNATIONAL INC
  • US9625892B2 patent drawing
  • US9625892B2 patent drawing
  • US9625892B2 patent drawing

AI summary

A system and method for monitoring device calibration. The system includes an asset management computer communicatively coupled to field devices. The asset management computer includes a processor connected to a memory device storing a field device drift identifying (FDDI) program. The FDDI program causes the asset management computer to statistically determine at least one process control limit from historical parameter data received from each of the field devices. The system continuously samples current parameter data received from each of the field devices and compares the current parameter data to respective ones of the process control limits for each of the field devices to determine whenever any of the current parameter data is outside the process control limit for identifying a first device drift for a first field device. Responsive to identifying the first device drift, an alert is generated that the first field device needs calibration.