Define the Time Zone to be used for Calculations within the Logic Program

If your Logic program makes use of time conversion functions such as MAKE_DATE_AND_TIME_FROM_OPC, it needs to be able to interpret the relative parts of the time values. For example, if an OPC Relative time is defined as 'DAY+5H', the program needs to be able to determine whether DAY begins at midnight UTC, midnight local time with Daylight Saving Time, or midnight local time without Daylight Saving Time. By default, a Logic program will use Coordinated Universal Time (UTC).

By using the Program Time Zone setting, you can choose which time zone is to be used when interpreting relative time values.

To change the Program Time Zone:

1. Display the configuration Form for the relevant program (see Configure an ST Program, Ladder Diagram, SFC or FBD).
2. Select the Logic tab.
3. Use the Program Time Zone combo box to choose the appropriate time zone setting for your Logic program:
   • Coordinated Universal Time (UTC)
   • Local Time without Daylight Saving Time
   • Local Time with Daylight Saving Time (for regional variations to GMT standard time, such as British SummerTime).

   The Program Time Zone setting that you choose is used for time conversions within the Logic program (the Interval Offset Time Zone setting defines the time zone that is used to determine when the program is executed—see Define the Interval Settings for a Logic Program).

4. Save any changes that you have made to the configuration.
   

Further Information

Date and Time.

Time Zones: see Time Zone Support in ClearSCADA  in the ClearSCADA Guide to Core Configuration.