Out-of-range alarming limitations

An out-of-range alarm occurs if at least one point value in the download list is out-of-range. As soon as all point values are within range again, and a data download occurs, the system generates a Return-to-Normal (within range) alarm. The following limitations exist for out-of-range alarming as seen on the Alarm Summary window.

Out of Range Checking is Not Compatible with Multiple Packet Download Lists

• When the Administrator chooses to allow multiple packets per download list download (via a key setting), and a download list is too big to fit into a single packet, then:

  • Out-of-range alarming (as seen in the Alarm Summary window) will not work properly.

  • The use of out-of-range checking is discouraged.

• The problem lies purely with out-of-range alarming as seen on the Alarm Summary window.

• The scheduler, as well as the Data Download Summary window, will still work as expected and warn of out-of-range values. In addition, the scheduler will not schedule data downloads for that list so long as at least one value is out-of-range.