ClearSCADA can communicate with devices that run in Coordinated Universal Time (UTC) or Local Time.
Internally the ClearSCADA server processes and stores time values in Coordinated Universal Time (UTC). For any feature or function that runs in Local Time, ClearSCADA converts the time from UTC to Local Time as required.
Each ClearSCADA Server and ClearSCADA Client obtains its time locally from the PC on which it resides.
You can specify on a per user basis as to whether times on a ClearSCADA Client are displayed in Local Time or UTC.
Of the outstations, PLCs and other devices and applications with which ClearSCADA can interact, many of these run in UTC. However, some outstations and other devices only run in Local Time, while others support being run in either UTC or Local Time.
With any device or application that runs in Local Time, the relevant ClearSCADA driver automatically converts the times that it receives from that device or application to UTC, before passing the times onto ClearSCADA. Conversely, the driver converts any times sent from ClearSCADA to Local Time, before passing those times on to any device or application that runs in Local Time. For more information, see Outstations with Clocks that Run in Local Time with Daylight Saving Time.
With devices for which the time zone setting is optional, ClearSCADA provides options on the relevant configuration Form, to allow you to specify the required time zone.
(Some devices support fewer options than those shown above.)
In ClearSCADA, various features—such as Historic Views, Schedules, and Logic Programs—can run in Local Time or UTC as required. With such features, configuration options are provided to enable you to specify the required time zone setting. Each of these features obtains its time from the ClearSCADA server.
For further information on any device or application for which the time zone setting is optional, see the appropriate configuration section in the relevant core or driver guide.
Further Information
Specify whether times in ClearSCADA are displayed in UTC or Local Time:
- for a named user: see Define the Regional Settings for a User in the ClearSCADA Guide to Security
- for a guest user: see Define the Global Settings for All Guest and Web User Accounts in the ClearSCADA Guide to Security
- on the clock that can optionally be displayed in the ViewX Status Bar: see Add a Clock to the Status Bar on a ViewX Client in the ClearSCADA Guide to Client Administration.
Local Time and The Effects of Daylight Saving Time Adjustments.
Script functions to convert time values from UTC to Local Time or vice versa: see LocalTimeToUTC, and see UTCToLocalTime in the ClearSCADA Guide to Scripting.
Logic functions to convert time values from UTC to Local Time or vice versa: see LOCAL_TO_UTC, and see UTC_TO_LOCAL in the ClearSCADA Guide to Logic.