The Application Calculation Engine (ACE) disabled on failover

If the Application Calculation Engine (ACE) points are being disabled on failover, it is likely because the ACE is trying to run something on the Standby computer that is causing an exception. There is a known race condition that can cause this to happen. It only affects one or two ACE points whenever it occurs, and from then on every point only executes on the Hot computer.

By default, the ACE catches DNAExceptions related to execution on the Standby computer and does not disable the ACE routine. However, if you are using these routines with non-baseline tables such as AVEVA Pipeline Operations for Liquids tables, these exceptions may not be caught and you may need to add try-catch statements to your code.