Errors and warnings in FBD

This section is intended for the errors/warnings that might occur when creating the logic within the →graphical FBD-editor (not provided in all variants of logi.CAD 3).

However, it is possible that errors/warnings occur for the FBD-editor as when


File contains syntax errors. Please fix them in the textual FBD-editor.
Solution, if the message is displayed after the command git pull: Open the →textual FBD-editor and resolve the conflict that has been caused due to the command git pull.
Solution, if the message is displayed because of other reasons: Contact the support team of logi.cals. Include your contact information, information on what you were doing in logi.CAD 3 and all messages listed in

the Error Log view, Problems view and/or PLC Logging view.
Include the faulty file as well.

Folder "name" does not exist. This folder is specified by the setting "lc3.fbd.themes".
As additional information: This message only occurs, if a system integrator has customized the default styles for the FBD-editor. The configuration variable lc3.fbd.themes is referring a folder that does not exist.
Solution for the user: Contact your system integrator and ask for a check/correction of the configuration variable lc3.fbd.themes.

Lines are not displayed because the line with ID "number" is connected to a non-existent FBD-element. Fix this error in the textual FBD-editor.
Solution : Open the →textual FBD-editor. Search for @G(specified-number), delete the faulty line (incl. the concluding character ;) and save the contents. Then try to open the POU within the graphical FBD-editor.

Lines cannot be routed due to overlapping elements.
As additional information: Usually, this warning is displayed for a POU that has been migrated from the predecessor product logi.CAD/32 to logi.CAD 3.
Solution: Move all overlapping elements in the POU so that the lines are routed.

Multiple variables within the same line of the declaration are not allowed. Just one variable per line is allowed.
Solution: Declare one variable per line (see "Declaring variables in FBD").

Invalid expression
Solution: In the faulty →value field, enter an expression according to ST.

There is no such function or function block.
Solution: In the faulty value field, enter another expression according to ST. Or make sure that the →function exists or an →instance of the →function block is declared before you enter it in the value field.

There is no such variable declared.
Solution: In the faulty value field, enter another variable. Or enter a new variable in the value field (see "Creating value fields or calls of blocks by using the content assist in FBD" for this possibility).

Variable already exists with a different data type.
Solution: Enter another →IEC-identifier (not yet existing) as name for the variable, when you create a value field with a new variable. Alternative: Enter only the name of the already existing variable in the value field (not the syntax for creating new variables). See under "Creating value fields or calls of blocks by using the content assist in FBD" for details.

Function blocks or interfaces are not allowed in functions.
As additional information: According to the →IEC-standard it is not possible to use a function block or an →interface within a function.

The structure contains a function block. But function blocks are not allowed in functions.
As additional information: According to the →IEC-standard it is not possible to use a function block within a function.

Only variables are allowed in this context.
Solution: In the faulty value field, enter a variable. Or use the value field in another context so that it assigns a value before you enter the expression in the value field.
As additional information: Only a variable is allowed in a value field that gets a value. A value field that assigns a value may contain an expression according to ST.

Too few inputs are connected.
Solution: Connect more inputs of the extensible →block to other FBD-elements by lines (see "Connecting FBD-elements by lines"). In case of a system block, the first 2 inputs must usually be connected for the correct functionality of the system block.

Assignment to this expression is not allowed.
Solution: In the →value field, enter a →variable onto which it is allowed to write. Alternative: Change the connection of the value field so that there is no assignment to it any longer. Afterwards it is possible to enter the →expression in the value field.
As additional information: →Assignments to →output variables or →literals are not allowed.

Invalid assignment.
Solution: Correct the →assignment so that a variable is entered in the affected value field. Make sure that it is allowed to write to this variable.
As additional information: Assignments to output variables or literals are not allowed.

"Character" is an invalid character.
Solution: Enter an →IEC-identifier as name for the variable, when you create a value field with a new variable.

This variable already exists.
Solution: Enter another →IEC-identifier (not yet existing) as name for the variable, when you create a value field with a new variable. Alternative: Enter only the name of the already existing variable in the value field (not the syntax for creating new variables). See under "Creating value fields or calls of blocks by using the content assist in FBD" for details.

An element with this name already exists.
Solution: Enter another →IEC-identifier (not yet existing) as name for the FBD-element.

Invalid variable type.
Solution: Enter one of the supported data types, when you create a value field with a new variable.

Invalid variable section.
Solution: Enter one of the valid abbreviations for the required variable section, when you create a value field with a new variable. Alternative: Omit the abbreviation (incl. :) in order to automatically create the new variables as internal variables (VAR). See under "Creating value fields or calls of blocks by using the content assist in FBD" for the valid abbreviations.

One or more elements do not exist.
Solution: In the →value field, enter the name of an already existing →variable. Or enter a new variable in the value field (see "Creating value fields or calls of blocks by using the content assist in FBD" for this possibility).

Assignment to element that does not exist.
As additional information: A line is highlighted as faulty. This line connects an FBD-element to a →value field. A →variable is entered in this value field but the variable is not declared.
Solution: In the value field, enter the name of an already existing variable. Or enter a new variable in the value field (see "Creating value fields or calls of blocks by using the content assist in FBD" for this possibility).

Missing or faulty function block declaration: name
Solution: Delete the set →instance of the →function block. Or declare the requested type so that the declaration exists again.

Function has not been found: name
Solution: Delete the set →call of the →function. Or declare the requested function so that it is found again.

In-/output is negated but not of ANY_BIT data type.
Solution: Delete the negation for the in-/output. Or change the data type of the in-/output to one of the following:

BOOL, BYTE, WORD, DWORD or LWORD(corresponds to →generic data type ANY_BIT)

Name is negated but not of ANY_BIT data type.
Solution: Delete the negation for the in-/output of the →call. Or change the data type of the in-/output to one of the following:

BOOL, BYTE, WORD, DWORD or LWORD(corresponds to →generic data type ANY_BIT)

Input is negated but not of ANY_BIT data type.
Solution: Delete the negation for the input of the →value field. Or change the data type of the input to one of the following:

BOOL, BYTE, WORD, DWORD or LWORD(corresponds to →generic data type ANY_BIT)

Output is negated but not of ANY_BIT data type.
Solution: Delete the negation for the output of the →value field. Or change the data type of the output to one of the following:

BOOL, BYTE, WORD, DWORD or LWORD(corresponds to →generic data type ANY_BIT)

Invalid negation of an unconnected value field input.
Solution: Delete the negation for the input of the →value field. Or connect the input of the value field with the output of another FBD-element.

Type conflict: The output with the type name cannot be assigned to the input with the type name.
Solution: Connect the output with a different input so that they are of an identical data type or of one that can be converted implicitly. Alternative: Correct the FBD-element accordingly – for instance, enter a variable with a correct data type in a value field or correct the data type for the in-/output of a block.

Strings with undefined length are not allowed.
Solution: Enter a maximum length for the STRING variable. See "Declaration of STRING variables (incl. access)" for more information on STRING variables with length.

Feedback loop at the function name.
Solution: Create a →value field in which you enter a →variable. Connect this value field to the in-/output of the function that is causing the feedback loop.

Feedback loops for functions are not supported.
Solution: Create a →value field in which you enter a →variable. Connect this value field to the in-/outputs of the functions that are causing the →feedback loop. A message in the "Problems' view lists these functions.

The input side of the VAR_IN_OUT variable "name" must be connected.
 Solution: Connect a value field with a variable with the input connection point of the →in-out variable.

The variable "name" is a VAR_IN_OUT variable. A literal must not be assigned to it.
Solution: Connect a value field with a variable with the input connection point of the →in-out variable.

The VAR_IN_OUT variable demands expressions to which a value can be assigned as well.
As additional information: This message is output either as error or warning. This depends on the debugging feature for FBD (by using the start option lc3.fbdDebugMemory).
Solution: Correct the assignment to the →in-out variable accordingly. Insert e.g. a value field containing a non-temporary variable.

The VAR_IN_OUT variable demands expressions with which a value can be connected as well. Hence, the connection from the output of the function block to the VAR_IN_OUT variable is neither allowed.
Solution: Correct the connection to the →in-out variable accordingly. Or deactivate the rule that is not allowing these connections.

Feedback loop for "name": A VAR_IN_OUT variable is connected exclusively to other VAR_IN_OUT variables.
Solution: Create a →value field in which you enter e.g. a local →variable. Connect this value field to the in-/output of the block that is causing the →feedback loop.

Faulty elements cannot be copied/cut.
Solution: Correct the faulty FBD-elements in the FBD-editor before you copy or cut them again.

No elements have been pasted because of a type conflict. This concerns the following variables: name
Solution: Adjust the →data type of the specified variables in the target object before you paste the elements again. Alternative: Copy just those FBD-elements that do not cause a type conflict and paste those.

No elements have been pasted because the function name does not exist in the project name.
Solution: Declare the →function in the target project before you paste the elements again. Alternative: Copy just those functions that exist in the target project and paste those.

No elements have been pasted because the function block name does not exist in the project name.
Solution: Declare the →function block in the target project before you paste the elements again. Alternative: Copy just those function blocks that exist in the target project and paste those.

Cannot hide EN/ENO because it is connected.
Solution: Delete the line connected to EN/ENO before you try to hide the EN and ENO again.

Not enough space to show EN/ENO.
Solution: Move the close-by FBD-elements before you try to show the EN and ENO again.

Function blocks are not possible in functions.
Solution: Delete the →function block that are highlighted as faulty.

The continuation name has no belonging connector.
Solution: Delete the →continuation. If you need →connectors and continuations, create a new connector and continuations.

Connector name has no continuation.
Solution: Create a continuation.

The connector name cannot be created because a unique name must be entered. But there is already an element with the same name.
Solution: Enter another name for the connector.

The variable name cannot be created because an element with the same name already exists.
Solution: Enter another name for the variable.

Forbidden circular reference between continuation and connector
Solution: Connect the continuation with another FBD-element or delete the faulty connection so that there is no circular reference any longer.

Invalid initial value for data type name.
Solution: Correct the initial value so that it matches the data type.

Invalid data type.
Solution: Enter one of the supported and existing data types, when you change the data type for a variable.

Invalid data type for initial value.
Solution: Enter a different data type so that it matches the initial value.

An internal error occurred while routing lines. Save, close and re-open the FBD-object before you continue editing the FBD-object.
Solution 1: After you have saved, closed and re-opened the affected FBD-object, also check whether the objects contains the last modifications. If not, repeat the necessary user actions.
Solution 2, if the message is displayed repeatedly: Contact the support team of logi.cals. Include your contact information, information on what you were doing in logi.CAD 3 and all messages listed in

the Error Log view, Problems view and/or PLC Logging view.

Global variables may be declared in programs only.
Solution: Do not declare →global variables in FBD function blocks or FBD functions but in FBD programs. Declare →external variables in FBD function blocks or FBD functions.

Changed interface: Variable name is located on a different position/orientation than it is displayed in the call for name.
Solution: Update the call for the block in the FBD-editor so that the current interface is displayed.

Changed interface: The variable name exists but it is wrongly displayed or not at all within the call for "name".
Solution: Update the call for the block in the FBD-editor so that the current interface is displayed.

Properties cannot be empty.
 Solution: Enter at least one property within the property field. Details on the syntax: see "Creating or editing properties fields in FBD"

Property key name is not unique.
Solution: Use unique keys for several properties within the property field. The key is entered on the left side of the assignment operator ":=".

Property does conform to the format "key1 := value1, key2 := value2".
Solution: Correct the properties so that they correspond to the mentioned syntax. Details on the syntax: see "Creating or editing properties fields in FBD"

Key name is not a valid IEC identifier.
Solution: Correct the key so that it is a valid →IEC identifier. The key is entered on the left side of the assignment operator ":=".

Assignment to connection point that does not exist
As additional information: A line is highlighted as faulty.
Solution: Delete the faulty line. Connect the corresponding FBD-elements by a new line.

The selected elements cannot be resized. There is not enough space.
Solution: Move the elements within the FBD-editor so that is sufficient free space. Then try again to resize the elements.

The selected elements cannot be aligned. There is not enough space.
Solution: Move the elements within the FBD-editor so that is sufficient free space. Then try again to align the elements.

A selected block cannot be made smaller because of a minimum height or width for the block.
Solution: Start the command Same Size for a different FBD-element so that the reference size is not below the minimum height or width of the block.

A selected step cannot be enlarged because of the maximum height for the step.
Solution: Start the command Same Size for a different FBD-element so that the reference size is not above the maximum height of the steps.

A selected transition cannot be enlarged because of the maximum height or width for the transition.
As additional information: It is not possible to enlarge a transition.

The name of the step must be an identifier according to IEC 61131-3.
Solution: Change the name of the →step so that the name is an →IEC-identifier.

A step cannot be pasted into a function.
or
A transition cannot be pasted into a function.
or
An action block cannot be pasted into a function.
→SFC elements (such as steps) are admissible within →programs and →function blocks only.

Invalid negation of an unconnected transition input.
Solution: Remove the negation for the transition input. Alternative: Connect the transition input with the output of a different FBD-element.

Invalid section. Variable must be a local variable or output variable.
or
Variable name for action block is not a local or output variable.
Solution: For the →action block, use a local variable or output variable but make sure that its data type is BOOL.

Invalid data type. Variable must be of data type "BOOL".
or
Variable name for action block is based on a data type that is not BOOL.
Solution: For the →action block, use a local variable or output variable but make sure that its data type is BOOL.

Illegal to write to variable name as it is used for an action block.
Solution: Use the local variable like a →constant variable. Alternative: Use a different variable within the action block.

Data type for variable used as action qualifier must be 'TIME'.
Solution: Enter a variable that has been declared with the data type TIME in order to define a duration for the action qualifier within the action block. Alternative: Enter a duration literal of data type TIME (see →Time literal for examples on duration literals).

Invalid action qualifier
Solution: Enter a valid action qualifier within the action block.

Duration of data type 'TIME' is missing for the action qualifier.
Solution: Enter a duration literal of data type TIME or a variable that has been declared with the data type TIME in order to define a duration for the action qualifier within the action block. Alternative: Enter a different action qualifier that does not need a duration.

The action qualifier does not require a duration.
Solution: Delete the duration literal or the variable that has been entered after the action qualifier within the action block. Alternative: Enter a different action qualifier that needs a duration.

Invalid connection.
Solution: Delete the connection of the →SFC elements. Some examples for allowed connections are listed under "Creating step sequences in FBD".

Invalid namespace "name".
Solution: Enter a valid →IEC identifier when the POU is declared within a namespace.

Namespace "name" already exists.
Solution: Enter a new, unique IEC identifier when the POU is declared within a namespace.

Missing namespace : name
Solution: Delete the namespace in the list of the used namespaces.

The call of the function or function block is too small because a minimum width has been specified. or
The call of the function or function block is too small because a minimum height has been specified. or
The call of the function or function block is too large because a maximum width has been specified. or
 The call of the function or function block is too large because a maximum height has been specified.
Solution : Resize the call so that it corresponds to the specified width/height.

Changed interface: The variable "name" is displayed in the call for "name" but it has not been declared as input or in-out variable. or
 Changed interface: The variable "name" is displayed in the call for "name" but it has not been declared as output or in-out variable.
 Solution: Update the call for the block in the FBD-editor so that the current interface is displayed.

The comment contains this invalid character: ' or
The description contains this invalid character: '
 Solution : Delete the invalid character from the comment or the description. Recommendation: Use the character " instead of the character ' within the comment and the description.

Invalid expression. Syntax: name := 'string'
Several lines must be separated by a comma ",".
Solution: Correct the content of the property field so that the properties are entered according to the syntax. See "Creating or editing properties fields in FBD" for details.

The instance parameter "name" could not be created.
As additional information: This message only occurs within a logi.CAD 3 variant that has been enhanced by a system integrator.
Solution for the user: Contact your system integrator and ask for a check/correction of the instance parameter.
As information for user and system integrator: The most probable cause for the error is that the variable has already contained instance parameter when it was tried to create the instance data for this variable.

Failed to enter the instance data for the variable "name".
As additional information: This message only occurs within a logi.CAD 3variant that has been enhanced by a system integrator.
Solution for the user: Contact your system integrator. Include your contact information, information on what you were doing in logi.CAD 3 and all messages listed in the Error Log view and/or Problems view.

OLT-fields must not be connected to functions inputs.
Solution: Create the OLT-field only for a valid element. Details: See "Creating or editing OLT-fields in FBD".

The value field for the variable "name" is missing within the type of "name".
The call displays a value field for the variable "name" but this value field does not exist in the type of "name".
Solution: Replace the existing call by a newly inserted call so that the most current interface of the type is used.

An empty value field is not allowed.
Solution: Enter a →literal or a →variable within the value field.

Interfaces are not allowed in this context. or
An element of the type is based on an interface. Interfaces are not allowed in this context.
Solution: Do not use →interfaces within the current editor.

Input "name" cannot be connected with multi-dimensional arrays. or
Output "name" cannot be connected with multi-dimensional arrays.
Solution: Use an array data type with one dimension.