s7-SCL-scripts/Times-scripts/FC_GetWeekNumber_readme.md

FC_GetWeekNumber

Description

Calculates the ISO 8601 week number (week 1 = week containing first Thursday)
Input: DT (DATE_AND_TIME)
Output: UINT (1..53)

Features

• Follows ISO 8601 rules (Monday week start)
• Uses built-in Siemens functions (WEEKDAY, DAY_OF_YEAR)

Input / Output

Input

• stDateTime : DT Date/time value

Return

• UINT Week number 1..53

Usage example

wCurrentWeek := "FC_GetWeekNumber"(stDateTime := #Now);
IF wCurrentWeek = 1 THEN
    // New year logic...
END_IF;