Tip: If you are viewing the Start Page, you can click Open One-line instead.
Maximize on the one-line window, if needed, to fill the session window with the one-line.The Transient Motor Starting (TMS) feature of EasyPower enables you simulate various power system events like motor starting, device switching, and bus faulting. It supports calculating voltage, current, speed, torque, and power for motors at various locations using EasyPower’s dynamic models. These calculated values are shown in time plots, spreadsheets and the one-line.
Note: If you have purchased only the Transient Motor Starting module and not the Dynamic Stability module, your menus and options will reflect the names "Transient Motor Starting" or "TMS" instead of Dynamic Stability.
To perform the steps in this tutorial, open the DSExample-1.dez file.
Tip: If you are viewing the Start Page, you can click Open One-line instead.
Maximize on the one-line window, if needed, to fill the session window with the one-line.Items on the one-line must have TMS data before you can run dynamic simulations.
Library to import the motor stability data from the library. Library to import the data. Library to import the data. 
Figure 1: Motor Stability Data
Figure 2: Motor Symbols in One-line
Note: If you have purchased only the Transient Motor Starting module and not the Dynamic Stability module, your menus and options will reflect the names "Transient Motor Starting" or "TMS" instead of Dynamic Stability.
Stability. The Stability tab is displayed as shown in Figure 3 and the windows
are arranged to view the one-line, the simulation plot and message log. As you enter the Dynamic Stability focus, EasyPower
runs a power flow solution for steady state. Note the power flow results on the one-line.
Figure 3: Dynamic Stability Tab
Figure 4: Motor Starting Results
The one-line shows the power flow results at the end of the simulation. The plot on the right shows values of motor voltage, current, speed and torque plotted against time. The message log window at the bottom describes what processes or events occurred. To view the spreadsheet data for this plot, you can drag the splitter bar at the left edge of the plot area to the right. You can format the plot axes or the plot area by double-clicking on the item.
Note: To perform any simulation commands, the one-line window needs to be the active window. If the title of the one-line window is not highlighted, click the one-line window once to make it active.
Figure 5: Simulation Data in Spreadsheet
Note: If you have purchased only the Transient Motor Starting module and not the Dynamic Stability module, your menus and options will reflect the names "Transient Motor Starting" or "TMS" instead of Dynamic Stability.
Click on the one-line window and select
DS Options from the
Stability tab. You can control the simulation through options in this dialog box.
In the Double-Click tab, note the controls for Breaker or Switch to Close. The default values are 6 seconds for Simulation End Time and 1 second for Delay Time Length. In the plot from the previous simulation, notice that the breaker BH-M-2 closed one (1) second after the start of the simulation, and the simulation plot ends at 6 seconds. You can control other double-click actions like bus faulting and ATS transfer in the same way.
When you perform a simulation by double-clicking on the one-line, data is plotted in the AutoPlot tab. Based on the type of simulation, EasyPower chooses which values to display in the AutoPlot. In the previous example, the plot was provided with motor per-unit values for voltage, current, speed and torque. To see values elsewhere in your system, you need to define plots. Nine plots are available with up to a maximum of 5 curves per plot.
Figure 6: Defining Plots
Define Plots. When motor M-2 starts, the voltage dip affects values at motor M-1. In Plot 1 we
view voltage, current, speed and torque for motor M-1. 
Reset Simulation to reset to steady state prior to any dynamic simulation. Start motor M-2 again by double-clicking on breaker BH-M-2. Click the Plot 1 tab to view the simulation results.You can write scripts to simulate various events and run them sequentially. Before we run scripts, we need to define plots so we can view results for the desired values. Next, we will write a script to simulate steady-state for 2 seconds, starting motor M-2, and switching off motor M-1.
Script Edit. 
Figure 7: Script Example
Run Simulation. View Plot 1 and Plot 2 of the plot window to see the results.
On the one-line window, double click on bus MCC-4.16. This runs a simulation of a 3-phase fault on this bus. The fault impedance and duration can be specified in DS Options > Double-Click tab. If you have the PowerProtector™ coordination feature enabled, TMS can simulate the response of a power system to a fault condition by causing protective devices to trip based on time-current curves. Notice the “C>>O” (closed-to-open) symbol on the tripped breaker in the one-line and the fault current dropping to zero in the AutoPlot. The Plot 1 tab shows motor M-1 fault current contribution and its subsequent spin-down after fault clearing.
This has been a brief tutorial on EasyPower’s TMS program. The EasyPower Help topics cover this and other features in greater
depth. To open Help, click 
Help in the upper-right corner of the EasyPower window or press F1.
With PowerProtector™, you can also simulate contactors dropping out because of excessive voltage drop, or an ATS switching to emergency power. Remember to enter data in the Stability tab of the various equipment data dialogs as necessary in the Database Edit focus first. Make use of scripts to simulate sequential events and use the Define Plots feature to monitor values.
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