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Smart instruments perform calculations locally inside field devices. Self-diagnosis becomes possible, and extends to the entire valve-instrument-controller closed-loop control application. Furthermore, the intelligence extends into the operating equipment as well, via vibration monitors, thermography and other online measurements. Smart diagnostics provide the basis for predictive maintenance, because problematic trends are often seen in the diagnosis long before they become catastrophic. Turnaround schedules can be fine-tuned to focus on equipment that truly needs servicing. The result is a shorter, more organized turnaround and lower overall maintenance costs.