Logic programs must be written by persons who have the necessary skills and knowledge related to the understanding, construction and operation of such programs. This knowledge includes, but is not limited to, having a thorough understanding of:
- The IEC 61131-3 standard
- ClearSCADA's Logic support.
Badly designed Logic programs can cause:
- Poor system performance (for example, through inefficient coding or configuration)
- Unintentional changes or activities to occur (for example, due to a program triggering the wrong device to change state).
Before using a Logic program in a 'live' system, thoroughly test all aspects of that program using a test system that accurately reflects the real system (including database size and data retrieval frequency). Perform further tests once the Logic program is installed on the real system to verify the correct operation of that program. It is important that arrangements for such checks are made and that sufficient time is allowed to perform complete and satisfactory testing.
WARNINGUNEXPECTED BEHAVIOR OF APPLICATION
Thoroughly test and monitor Logic programs:
- In a simulated environment that accurately reflects the real system
- In the real environment
before relying on the operation of those programs in a 'live' system.
Store all documentation for future reference.