Manage Faults in Referenced Models

You can add faults to individual instances of referenced models in the parent model, or add faults to all instances of the referenced model by modifying the referenced model faults directly. If you modify the faults in the referenced model, you must synchronize the changes in the referenced model to the parent model.

Add Faults to Referenced Models

You can add faults to an individual instance of a referenced model or to all instances of a referenced model.

Add Fault to Single Referenced Model Instance

To add a fault to a single instance of a referenced model:

1. Open a model that contains a referenced model.

2. Open the referenced model by double-clicking the Model block.

3. Add a fault to the referenced model. Select a signal and, in the Fault Analyzer tab, in the Prepare Faults section, click Add Fault. In the Add Fault window, specify the fault properties, then click OK.

4. Save the parent model. The fault appears only in that instance of the referenced model. The software updates the fault information file of only the parent model.

Starting in R2025a, you can copy faults into referenced models. See Copying Faults.

Access Faults in Referenced Model From Parent Model

To add faults to all instances of a referenced model, add faults to the referenced model while it is open as a standalone model. However, when you add a referenced model to a parent model, Simulink^® Fault Analyzer™ does not automatically copy the faults in the referenced model to the parent model. To introduce the faults to the parent model, you must synchronize the fault information files. Synchronizing copies the faults from the referenced models to the parent model.

To create faults in a referenced model and synchronize the faults with the parent model:

1. Open the referenced model as a standalone model.

2. Add faults to the model. Select a signal and, in the Fault Analyzer tab, in the Prepare Faults section, click Add Fault. In the Add Fault window, specify the fault properties, then click OK.

3. Save and exit the model. The software stores the fault information in the fault information file of the referenced model.

4. Open the parent model that contains the referenced model and synchronize the faults. In the Fault Analyzer tab, in the Prepare Faults section, click Resync Faults.

If you click Resync Faults in a parent model that does not have faults, Simulink Fault Analyzer creates the fault information file for the parent model in the working folder.

The synchronized faults appear in the parent model and their names include the name of the Model block, followed by the name of the fault. To save the model, the synchronized faults, and the fault behaviors, in the Fault Analyzer tab, in the File section, click Save All.

Configure Referenced Model Fault Properties

You can access the fault properties of the faults that you add directly or the synchronized faults from the parent model. To access the properties:

1. Open the Fault Table pane. In the Fault Analyzer tab, in the Prepare Faults section, click Fault Table. The faults appear in the table. The path includes the name of the referenced model.

2. Right-click the fault and click Properties to view the properties in the Property Inspector.

This image shows the Fault Table pane for a parent model with two faults. The parent model contains a referenced model. The parent model contains one fault, Sine_Wave_Outport1_fault, and the referenced model contains another fault, Model_Inport_Outport1_fault. The Fault Table pane displays the faults available to the parent model.

The model element path corresponds to the name of the Model block that contains the fault. If you update the name of the Model block that contains the faults, the model element path updates automatically. If you update the name of the Model block name and synchronize the fault information files, the synchronized fault names also update.

Example Referenced Model with a Fault

This example shows how a referenced model that contains a fault interacts with a top model. The referenced model also contains a fault that only appears in this instance of the model. To view the parent model, open the mdlref_basic_1 model.

The parent model contains two faults. One of the faults originates from the referenced model, and the other originates in the parent model. From the top model, open the ModelA referenced model to view the faults.

The fault information file of the parent model, mdlref_basic_1_faultInfo, stores information from the faults in the parent model and the referenced model. The Fault Table pane indicates whether the faults originate in the referenced model or the top model. Open the Fault Table pane and expand the model elements to view the faults.

The faulted_counter model has its own fault information file, as does the parent model mdlref_basic_1. You can also add faults to the referenced model and synchronize. In this example, add a fault to the output port of the And block in the faulted_counter model and synchronize the new fault in the mdlref_basic_1 model.

1. Open faulted_counter as a standalone model.

2. Select the output port signal from the And block.

3. In the Fault Analyzer tab, in the Prepare Faults section, click Add Fault. In the Add Fault window, click OK.

4. Save the model, the faults, and the fault behaviors. In the File section, click Save All.

5. Exit faulted_counter.

6. In the mdlref_basic_1 model, synchronize the fault information. The Fault Table pane shows that the parent model now has a copy of the fault you added.

Store and Use Faults from Multiple Instances of a Referenced Model

If the top model contains more than one instance of a referenced model that contains faults, and you synchronize the model, Simulink Fault Analyzer stores the fault behaviors for the instances in different fault models. The fault model depends on the order that the referenced model is added to the parent model during synchronization:

• For the first instance of the referenced model, Simulink Fault Analyzer uses the fault behaviors in the original fault model used by the referenced model.

• For additional instances of the referenced model, Simulink Fault Analyzer stores the fault behaviors in a new fault model whose name ends with the text FaultRefModel.

For example, suppose a parent model contains two Model blocks, Model1 and Model2, that both reference the model myRefModel. myRefModel contains faults and uses the fault model myRefModel_faultModel to store the fault behavior. When you synchronize the faults in the parent model, the fault behaviors that the parent model uses for Model1 are stored in myRefModel_faultModel, and the fault behaviors that the parent model uses for Model2 are copied into a fault model called myRefModel_FaultRefModel.

Example with Multiple Instances of a Referenced Model with a Fault

This example shows how a model with multiple instances of a model reference stores faults. To view the parent model, open the mdlref_basic_2 model.

The parent model contains two instances of the same referenced model, faulted_counter. The parent model contains one fault that exists only on the Switch block in the instance of ModelA. However, the parent model is not synchronized, and faulted_counter contains an additional fault on the Add block. The instances of this fault in ModelA and ModelB do not appear in the parent model.

Because the model is not synchronized, the fault information file of the parent model, mdlref_basic_2_faultInfo, contains only one fault. Open the Fault Table pane to view the fault.

In the Fault Analyzer tab, click Resync Faults to synchronize the faults. Because this example uses two instances of the same referenced model, the top model copies the fault behavior of the second referenced model, ModelB, and stores it in a separate fault model, mdlref_basic_2_FaultRefModel. The faults now appear in the Fault Table pane.

To save the model, the faults, and the fault behaviors, in the Fault Analyzer tab, in the File section, click Save All.