Placing coils

Introduction

Coils can be placed in any free cell except cells directly on the left power rail.

If all coils are to be placed on the right power rail, select the Tools > Project Settings menu, and in the Program > LD tab, check the Right-justify coils checkbox.

If a coil is placed in a cell that is already occupied by a Boolean link or a label, the cell contents are replaced by the new coil.

If a coil is placed in a cell that is already occupied by a coil, or a contact, a confirmation message is returned to replace the cell contents by the new coil.

If a coil is placed in a cell that is already occupied by another object and can not be replaced (e.g. FFBs), an error message is returned

NOTE: The above behavior maybe different when Insert Mode is activated.

A placed coil automatically creates a connection with its neighboring objects on the left and right if they are of the BOOL data type, even if free cells are between them.

The following are permitted as actual parameters for coils:

Boolean variables
Boolean addresses (topological addresses or symbolic addresses)

Note

In the Tools > Options dialog box on the Data and Languages > Languages tab, if the Automatically assign a variable to a new graphical object checkbox is selected, then the corresponding properties dialog box is automatically opened when an object is placed. The procedures explained here are used when the checkbox is cleared.

Placing Coils

Step	Action
1	Select the desired coil.
2	Click the target cell in the LD section. or Use the arrow keys to move the gray field to the target position, and press Enter. Result: The selected coil is inserted. In the Tools > Project Settings dialog box, on the Program > LD tab, if the Right-justify coils checkbox is selected and the last cell in the current row (cell directly on the right power rail) is not occupied, the coil is placed automatically on the right power rail. If this cell is already occupied, the coil is inserted into the current cell (cursor position gray field).
3	To place further coils of the same type: Click the target cell in the LD section. or Use the arrow keys to move the gray field to the target position and press Enter. To return to selection mode: Press the Esc key. To insert other objects: Select the object you wish to insert.

Step

Action

Select the desired coil.

Click the target cell in the LD section.

Use the arrow keys to move the gray field to the target position, and press Enter.

Result: The selected coil is inserted.

In the Tools > Project Settings dialog box, on the Program > LD tab, if the Right-justify coils checkbox is selected and the last cell in the current row (cell directly on the right power rail) is not occupied, the coil is placed automatically on the right power rail. If this cell is already occupied, the coil is inserted into the current cell (cursor position gray field).

To place further coils of the same type:

Click the target cell in the LD section.

or

Use the arrow keys to move the gray field to the target position and press Enter.
To return to selection mode:

Press the Esc key.
To insert other objects:

Select the object you wish to insert.

NOTE: When editing a program in Ladder, a short circuit on a coil may lead to a state always true. For a good logic behavior, the short-circuit must be deleted..

If the short-circuit (1) is located on top of the coil B2, this coil will remain in a true state (B2 = 1) regardless of the logic activating the coil C1. As a consequence, the active state (2) is propagated to the following logic (b4 = 1).

Assigning actual parameters

Assigning actual parameters:

Step	Action
1	Open the properties dialog box for the coil. Result: The coils properties dialog box is opened. Example:
2	You have the following options to enter the actual parameters: You can now enter the variable/address name and confirm using Enter. You can select the variable name from the list of recently used names using the symbol and confirm using Enter. or Using the button ... you can open an Instance selection dialog box and confirm the selected variables there with OK. Example of a variable selection dialog box:
3	Confirm the selected variable with OK. Result: If the selected variable is declared, it is enabled in the section. A syntax and semantics check is performed and the procedure ends here. If the variable is not declared, a variable declaration dialog box opens. In this case, continue with the following steps of this procedure. Variable declaration dialog box Note: If you wish to declare the variable later, close the dialog box using the symbol. In this case, the variable name is enabled in the section, but not declared.
4	If you do not want to assign the variable an address or comment, confirm using Enter or the symbol. Result:The variable is declared and enabled in the section. A syntax and semantics check is performed and the procedure ends here. Example:
5	If you do want to assign the variable an address and/or comment, use the symbol for obtaining an advanced dialog and enter the address and/or comment.
6	Confirm with Enter or the symbol. Result:The variable is declared and enabled in the section. A syntax and semantics check is performed. Example:

Calling a subroutine

Calling a subroutine:

Step	Action
1	Place a call coil in the section. Note: Subroutine calls are expansions to IEC 61131-3 and must be explicitly enabled via the Tools > Project Settings dialog box, in the Program > Languages > Common tab by selecting the Allow subroutines checkbox.
2	Open the properties dialog box for the coil. Result: The coils properties dialog box is opened.
3	Click the symbol and select the subroutine to call from the list and confirm using Enter. Note: The subroutine to be called must be located in the same task as the LD section called. Result: The subroutine call is inserted into the section and a syntax and semantics check is performed. Example: If the subroutine has already been created, the procedure ends here. If the subroutine has not yet been created, continue with step 4.
4	Create the subroutine.