Example Return to Nominal Scenarios
The following scenarios shows using Return to Nominal for switching actions on the diagram to the right..Illustration of a network with open and closed devices and their source breakers.
Example 1
Simple load balance planned switching action.
1. The user creates a Planned Switching sheet to move load from one pressure zone to another:
• Open B -- make a parallel
• Close A -- break a parallel
• Open D -- make a parallel
• Close C -- break a parallel
2. The user switches to Real Time mode and executes the steps.
3. The user clicks the button to generate Return to Nominal steps.
4. The switching plan will add the following new steps to the bottom of the plan, in a new Return To Nominal block:
• Open C -- make a parallel
• Close D -- break a parallel
• Open A -- make a parallel
• Close B -- break a parallel
Reviewing a Switching Sheet in Study Mode
You can review the actions of a switching sheet in a Viewer window. With the Viewer and the switching sheet in Study Mode, you can complete steps by selecting a step and clicking the Complete button on the Steps tab toolbar.
As the steps are completed, each one takes effect in the Viewer window and the words "ST Completed" appear in the Status column in the steps section. Steps are completed starting with the first step and continuing sequentially; however, it is possible to complete steps out of order based on the type of switching sheet and whether the step is in a step grouping or not. (See “Step Order Execution Rules” for more information.)
The Look Ahead window informs you of the results of the operation, including the creation of parallels and loops, the number of critical customers affected, and related abnormal assets and conditions.
Replaying Steps
You can replay steps in the Viewer window, allowing you to experiment with and make changes to a switching sheet. You can then add and delete switching steps and then select one of the three Reset Study Session options (see Reset study session and clear the status of the steps on page 10-30 for more information). After resetting your study session, you will be able to go through the steps again using the Complete button.
Implementing a Planned Switching Sheet
Once you have created, studied, and approved a switching sheet, you can implement the plan. Implementing involves the following steps:
• Issuing a Switching Sheet (includes associating a crew and printing the sheet)