Naming Rules

The rules for what is a valid or invalid name will vary according to the type of thing you are naming.

Naming Rules for Applications

In general, applications are stored in a path that matches the name. The rules for application path names are more strict than for application names because the path must be a valid Windows folder name. Application names may include alphanumeric characters, and can include the punctuation key symbols (i.e. decimal (.), and comma (,)), and symbols created using the number keys (for example, the number hatch (#), and underscore characters (_)).

If the application path name is based on the application's name, VTScada automatically removes any invalid characters and spaces. If you attempt to name an application "." (period), then VTScada will append a "1" to the path name because "." already exists as the name of the current windows folder.

The characters in the following table may not be used in application path names. If you choose to enter a custom application path, you cannot use these invalid characters or spaces.

Invalid Character Example
Colon :
Less Than <
Greater Than >
Pipe |
Backslash (other than as a divider between folder names) \

Naming Rules for Pages

Valid characters that may be used in page file names consist of any combination of:

  • Alphanumeric characters (i.e. A through Z, and 0 through 9)
  • The underscore character ( _ )
  • The decimal character ( . )

Page names can include other symbols (e.g. dollar sign ($), number hatch (#), equals (=) characters), spaces, or strictly numeric characters, but not in page file names. Because these symbols are acceptable in page titles, and the page file name is automatically based on the page title, VTScada strips any invalid characters when generating the page file name.

Note that widget names cannot be the same as the short name of any tag.

Naming Rules for Tags

  • Tag names must be no longer than 64 characters in length

This rule refers only to the tag's immediate name, not its full name, which may include a lengthy list of parent tags.

  • Full tag names must be no longer than 253 characters in length

This rule refers to the tag's full name, which may include many parent tags.

  • Tag names must not duplicate other named items (reserved words).
    • You cannot name a tag "TagBrowser" or "Test", since those names are used elsewhere in VTScada.
    • A tag may not be named "Value" or "Area" since those are the names of tag properties.
    • Tag names may not duplicate Type names - you cannot name a tag "Calculation" or "Analog Status".
    • Tag names may not duplicate any function names. Refer to Function Reference.
    • In general, it is safest to avoid using common words unless you add a prefix or suffix.
  • Valid tag name characters include:
    • Any combination of alphanumeric characters (i.e. A through Z, and 0 through 9)
    • Spaces, except at the beginning or end of the name.
      (Some installations choose to avoid spaces as they can cause confusion. For example, "A B" looks like "A  B" but the second has two spaces and is therefore a different name.)
    • Period
      (Legal but discouraged.)
    • Symbols other than those listed below.
      (Underscore _ and dash - characters are used in place of spaces at installations where spaces are avoided.)
  • Invalid tag name characters include:
    • Backslash (\ which used to separate parent names)
    • Forward slash (/)
    • Colon (:)
    • Asterisk (*)
    • Question mark (?)
    • Double quotes (")
    • Less than (<)
    • Greater than (>)
    • Vertical bar (|)
    • Leading spaces
    • Trailing spaces
  • Tag names cannot be purely numeric.

"51" is not a valid tag name but "Station 51" is.
An interesting side effect of this rule is that you cannot name a tag "E1" or similar since this is a valid numeric expression: ("E1" == "0E1" == "zero exponent one").

In the event that you have entered an invalid tag name, VTScada will notify you with a warning dialog and will clear the Name field so that you can try again.