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Here are some steps and some advise to program a SFC without troubles:

Draw your level1 diagram

After creating a new SFC program, you have already the initial step drawn.

• Simple elements: transitions and steps

Select the icon to insert a transition below the initial step.

Put the cursor below the initial step as follows:

• Automatically the Transition is connected to the initial step and you are ready to place a step.

Continue to draw you chart as done for this transition.

• Divergence

If you have to place a divergence, select the correct icon:

OR divergence (single line) after a step

AND divergence (double line) after a transition.

Place the cursor below the step or the transition.

• Adding a new branch to a divergence

If you have more than 2 branches to your divergence, first connect elements of the 2 first branches, then select your divergence and click on the New branch icon on the toolbar ().

• Convergence

To place a convergence, click on the correct Convergence icon on the toolbar:

OR convergence (single line) after transitions

AND convergence (double line) after steps.

Place the cursor below the last element of the left-most branch.

• Tricks and Tips

• If you made an error, prefer the use of the following sequence rather than the use of Undo.

- Select the element to delete
- Press the "Del" Key
- Remake your diagram as you wish.

• If you want to insert some steps or transition within an existing diagram:

- Delete the link where you want to insert the elements
- Move all the elements below (select all elements below, and use drag and drop operation)
- Continue your diagram from the last element of the first part of the diagram.
- Move back the part you have moved to connect to the new inserted elements.

Caution: for the diagram to re-connect, you must remind that automatic connection is done only between a step and a transition and vice-versa.

Program the "level2s"

• Open the level2 window

To open the level2 window, click on the step or transition and press Return.

CAUTION: do not use double-click to open level2 window, as it may lead to rename the step or transition, or give the focus to the level2 preview in the level1. If you have done that by inattention, just click in an empty space in the level1 workspace.

• Select the language

When the level2 window is open, select the language in the selection list by clickin on the left part of the title of the action or condition.

• Change the name of the action or the transition

Click on the right part of the title and give an IEC61131 name (no special character - no space ...) and press Enter.

• For actions, select the action qualifier (N, S, R, P1, P0) in the selection list by clicking on the left-most part of the action title.
• To edit the code of the action or the transition when it is in LD or ST or IL, click in the main part of the level2 window.
• When you have an action of type Boo, a dialog box is shown for you to select or enter a boolean variable.

• Caution: after having selected the variable, the editor automatically scrolls to the next action block. If you want to go back to the action block you were defining, click up on the scrollbar on the right of the level2 window.

• If you want to change the variable, click on the variable (action title). A small button is displayed on the right of the action title. Click on this button to select another variable.

• When you have an action of type SFC Child, enter directly the name of the SFC child in the action title.

• To go to the next or the previous action block use the scrollbar on the right of the level2 window.

• Tricks and Tips

• If you made an error in the list of action blocks of a step, if you want to delete or change the position of an action block:

- When an action block is currently selected, use the Options / Show Level2 as List command
- In the list shown, select the action block you want to delete or move
- Use the buttons of the toolbar to delete or move
- Use the command Options / Detail level2 to go back to the normal mode for editing or modifying an action block.

• If you want to insert a new action,

- Use the Options / Show Level2 as List (as detailed above),
- Select the action block that will come after the new inserted action block
- Use the button in the toolbar.
- Use the command Options / Detail level2 to go back to the normal mode for editing or modifying an action block.

• To save your program, always give the focus to the level1 before using the Save command.

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