The One-Line represents power flow of the distribution system shown from top to bottom, and generally consists of Sources, Distribution Equipment, and Loads. Types of sources include a Utility or a Generator.
Using the Workspace Toolbar on the left, click the One-Line icon to open the Workspace.
Add a Source¶
Use the Setup Wizard in the top right and select Create a Source.
Sources specify the level of short circuit current (SCC) that is potentially available in faulted systems. Short circuit current contributions could stem from the generator’s sub-transient reactance or the utility takeoff secondary terminals.
Using the New Network wizard, create a Utility Equipment.
When using the New Network wizard, only the minimum pieces of information are required to create a piece of Equipment. This information will vary from Equipment to Equipment. For example, when creating a transformer the secondary voltage must be specified, but for a mechanical load only the size of the motor is required. More detailed properties can be specified and modified later.
Or right-click inside the Workspace, click Add Source, then click Utility Source.
Note that the ability to add Unhosted Equipment is available.
Short Circuit Current¶
Select the Utility source. Under the “Miscellaneous” property grouping, enter the value under Available SCC (kA).
Click on the Utility and the Selection Dial will display a ring of options. Selected Equipment will be highlighted by a purple circle, with additional options to Add, Copy, Paste, Delete, and Navigate to other Workspaces. Click the + button to Add Equipment.
Select an Equipment type from the dropdown menu. Give the Equipment a name. In this case, specify a Load Capacity, and click Select.
To copy Equipment, select the Equipment. Then, click Copy or use CTRL+C to copy. The selection will highlight pink and be added to the clipboard.
Then select the Equipment you want to create a pasted copy of, and click Paste or use CTRL+V.
Delete Equipment/Delete Network¶
To delete Equipment, select the Equipment. Then Click Delete (trash symbol) or use DEL to delete.
If the selected Equipment is feeding downstream Equipment, you have the option to either delete the selected Equipment or the entire network. Deleting Selected Equipment will only delete what is selected and any downstream equipment or children of the Selected Equipment will be disconnected and considered Unhosted.
To redirect an Equipment’s source, click and drag the Equipment from its current source to a different source.
Sections of the distribution network can be expanded or collapsed on a group basis by using Expand All/Collapse All.
Another way is by clicking on a distribution node, or double-clicking on the Equipment itself.
Changing Multiple Equipment Properties¶
It is possible to change a property which is common across multiple elements.
First, drag a box to select multiple elements, or use CTRL+Click to select each element.
Then change a property such as Conductor Material from copper to aluminum.
Note that since Design Assistance is on, the circuit’s code-minimum values are recalculated.
Reset to Code Minimum¶
It is possible to manually modify circuit elements which cause a violation of safety codes and standards.
To recalculate or reset the values of a circuit to code-minimum values, right-click on an Equipment and use Reset to Code Minimum.
Utility functions like searching, additional viewing properties, or calculation settings can be found on the Workspace Toolbox on the top toolbar.
To search for Equipment, click the magnifying glass in the top left. Start to type the name of an Equipment. A dropdown will appear with any Equipment matching the specified name. Select the Equipment, and the Workspace will navigate to the associated Equipment.
One-Line View Selectors¶
Different Views such as Isolated Systems and Load Flow can be applied to aid the designer.
By default, Normal is selected.
Load Flow is recommended when studying how a system is loaded.
Isolated Systems is recommended when viewing complex, redundantally distributed systems.
Click on the arrow buttons to jump to the section of the distribution network.
Creating a Transfer Switch¶
Transfer switches are connected to a primary and secondary source of power. To create a transfer switch, click Add Equipment and choose ATS/STS.
To connect the secondary source of power, choose another distribution Equipment.
Then click Add Equipment and select an ATS/STS from the Existing dropdown menu.
Toggle the visibility settings of OCPD’s by clicking on Show OCPD.
Open an OCPD by clicking on the OCPD.
The Scenario Manager can be used to model different scenarios representing the state of protective devices. It is generally used in conjunction with the One-Line.
For example, a designer may want to perform a load flow study of their electrical system as certain protective devices are opened or closed.
Open the Scenario Manager and show the OCPD’s on the One-Line.
Right-click on a protective device to add it to a Scenario.
In each Scenario, toggle the different states of protective devices, and also toggle between different Scenarios as shown below. Note that the color of live Equipment changes when a protective device is opened or closed.