What makes InduSoft Web Studio such a unique SCADA software package is the fact that all necessary tools such as trends, reports, recipes, and database connectivity are all included within the software. One important built-in feature of IWS is the Event Logger, which records and logs a variety of events.
The IWS Event Logger can record data either in the proprietary InduSoft format, or in any SQL database, such as Microsoft SQL Server, MySQL, Oracle, and more. To configure the Event Logger, merely check off the boxes of events you wish to record. Some logged event options are:
- Security system
- Display screens
- Custom messages
- System warnings
- In addition, operators can log any tag, or attach dedicated messages to logged tags.
Why Log Events?
It’s important to log events in your SCADA or HMI system. Many problems within the plant or equipment may occur when no one is monitoring the system, and intermittent problems may be difficult to diagnose without a history of previous issues. Automated logging of events like security and system warnings give operators and plant managers a chance to review older data in order to look for previously overlooked issues, or to catch up with any missed notifications. In conjunction with the event logger configuration (shown in figure 1), the Alarm/Event control object displays the history of the events.
Another important reason to log events is to add traceability. By monitoring who logs into the system, and what they do, accurate records can be prepared for things such as compliance with FDA 21 CFR Part 11, and USDA regulations.
Custom Messages in the Event Logger
The ability to create custom messages is another useful feature within the Event Logger. This is accomplished by using the “SendEvent()” function.
- SendEvent( “Valve Open Oven No. ” + OvenID ) // Saves the event message with the value of the OvenID tag.
- SendEvent( “Valve Open” , 1 ) // Displays the dialog where the operator can type comments.
When logging tag events, in addition to messages, a dead band can be applied
For example, if you specify a Dead Band value = 5, for a tag value = 50 and the tag value changes to 52, the system will not register this variation in the event log file, because the variation is less than 5. However, if the tag value change is equal to or greater than 5, the system will save the new value to the history file.