4.6 Automated Diagnostic Analysis

The automated diagnostic analysis generates sensor sets, i.e. a collection of flow properties that the user can allocate sensors to. These sensor sets are by default optimized to achieve maximum coverage of the system or level of indenture selected by the user.

To create a new Automated Diagnostic analysis:

1. Select New
2. Select the checkbox for level of indenture to be investigated in the system
3. Select the Automated radio-button, then select Next
4. Enter the Name and Description for the analysis
5. Verify the Propagation type (either Bond or FCM — this is automatically set)
6. Select Finish to complete the process

4.6.1 Diagnostic Analysis Page

After a new automated diagnostic analysis is created, the analysis page is automatically opened. This page allows the user to manage diagnostic analysis details, options for level of indenture selection, and the ability to focus on specific flow categories.

4.6.1.1 Basic Details Section

This section consists of name, description, diagnostic analysis type, propagation type and response state fields. The first four fields are automatically filled out based on information entered in the New Diagnostic Analysis dialog. Name and Description fields can be edited by the user at any time, while Diagnostic Analysis Type and Propagation Type are fixed.

The response state field consists of a drop-down menu with 3 options:

• Steady State (Default) — The system state reached following a failure once a constant flow response (i.e. non-fluctuating) has been reached by items within the system.
• Transient State — The system state immediately following a failure with each flow property exhibiting a high, low, or no deviation from its nominal level.
• Steady and Transient States — An option that considers both steady and transient states in the diagnostic analysis.

4.6.1.2 Indenture Selection Section

This section consists of a tree diagram which shows all levels of indenture, including the system and all subsystems. The tree diagram shows which levels of indenture are considered in the automated diagnostic analysis, however the user can choose to include or exclude additional levels of indenture or subsystems.

Note: When an inclusion is assigned or a sensor set analysis is created, the indenture selection section is locked into a read-only state. To edit (include/exclude) subsystems, the current sensor set analysis page must first be deleted or cleared of generated/user sensor sets.

4.6.1.3 Propagation Focus Section

The Propagation Focus section shows a list of flow categories, types and properties in the system. This section restricts or filters the scope of the sensor analysis by excluding unselected flow properties. All selected flow properties in the Propagation Focus section will be included in the diagnostic analysis. If no flow properties are selected, all flows will be analyzed by default.

To specify a Propagation Focus:

1. Select the checkbox of a flow property to be included in the diagnostic analysis

4.6.2 Propagation Table Page

This page shows the propagation table used for the automated diagnostic analysis. The propagation table is automatically generated and is derived directly from the system model. It is one of two sets of data interrogated for sensor set analysis, the other being the observed failure responses that each sensor in the set may detect.

The table consists of:

• Initiating causes of failures listed in the left-most columns (Item, Flow Property, Failure)
• Item Responses for remaining columns across the table
• The healthy system state (first row), which represents the system at a nominal state, is included in the propagation table to ensure a sensor set can observe a failure occurrence

Each cell contains one of three failure responses (terminology may vary depending on flow property selected):

• Nominal
• Low / Misaligned − / Misdirected − / Displaced + / Misshapen + / Advanced +
• High / Misaligned + / Misdirected + / Displaced − / Misshapen − / Advanced −

The propagation table considers all exclusions in the diagnostic analysis by displaying a blue highlight over rows (causes of failures) or columns (its responses). A refresh icon is located above the table to update the Propagation table when changes are made to the model.

4.6.3 Inclusions Page

This page is used to specify the failures and sensor locations that must be covered or included in the diagnostic analysis. The options on this page constrain the analysis so that specified failures are always uniquely identifiable and that sensor locations are always included in every sensor set.

4.6.3.1 Must Cover Failures section

This section consists of a table for the user to select and include failures that must be uniquely identifiable by each sensor set created in the diagnostic sensor set analysis.

To include uniquely identifiable failures:

1. Select the plus icon to open a new dialog
2. From the Available Failures table, select either an item or Failure Mode
3. Select the right-facing arrow to include the selection in the Selected Failures table
4. To undo an inclusion, select the item/failure mode and select the left-facing arrow
5. Select OK to close the dialog and apply the changes
   • Alternatively, select the item/failure mode, then select the delete button to remove it

4.6.3.2 Must Use Sensor Locations section

This section consists of a table for the user to select sensor locations. These sensor locations will be included in all sensor sets created in the diagnostic sensor set analysis.

To include uniquely identifiable failures (sensor locations):

1. Select the plus icon to open a new dialog
2. From the Available Sensor Locations table, select either an item or Failure Mode
3. Select the right-facing arrow to include the selection in the Selected Sensor Locations table
4. To undo an inclusion, select the item/failure mode and select the left-facing arrow
5. Select OK to close the dialog and apply the changes
   • Alternatively, select the item/failure mode, then select the delete button to remove it

4.6.3.3 Legacy Sensor Set Section

This section contains a table that displays all component/subsystem test point locations belonging to a legacy sensor set. Selecting the checkbox will include these test points and sensors (if allocated) in the diagnostic sensor set analysis.

4.6.4 Exclusions Page

The Exclusions page allows the user to remove initiating failure events or sensor locations (sensed flow properties) from the automated diagnostic sensor set analysis. This may be due to unnecessary or infeasible detection of certain failures. Creating exclusions automatically updates the propagation table — exclusions are indicated in the propagation table rows/columns with a blue highlight.

4.6.4.1 Criticality Thresholding Section

This section consists of a critical measure area where the user can select the criticality type and value, and a Criticality Cause Exclusions table, which shows the exclusion results of the criticality applied.

To exclude failure causes based on criticality:

1. Select a criticality type by left-clicking the radio button
2. Set the Threshold amount by selecting the numerical field or drop-down menu
3. Select Apply to run an analysis
4. Verify that the Criticality Cause Exclusions table shows results that are now excluded

4.6.4.2 Detectable Cause Exclusions section

This section contains a table which displays components, subsystems and their respective flow properties, which are considered detectable causes that are excluded from the sensor set analysis.

To exclude detectable causes:

1. Select the plus icon to open a new dialog
2. From the Exclusion — Detectable Failures dialog, select an item or Failure Mode
3. Select the right-facing arrow to exclude the selection in the Excluded Failure Modes table
4. To undo an exclusion, select the item/failure mode and select the left-facing arrow
5. Select OK to close the dialog and apply the changes
   • Alternatively, select the item/failure mode followed by the delete button to remove it

4.6.4.3 Sensor Location Exclusions section

This section consists of a table for the user to select and exclude sensor locations that will not be considered by each sensor set created in the diagnostic sensor set analysis.

To exclude uniquely identifiable failures (sensor locations):

1. Select the plus icon to open a new dialog
2. From the Detectable Failure Modes table, select either an item or a Failure Mode
3. Select the right-facing arrow to include the selection in the Excluded Failure Modes table
4. To undo an exclusion, select the item/failure mode and select the left-facing arrow
5. Select OK to close the dialog and apply the changes
   • Alternatively, select the item/failure mode, then select the delete button to remove it