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Control Execution The Ovation OCR1100 controller, with an Intel®-based processor, is capable of simultaneously executing as many as five process control tasks at loop speeds ranging from 10 milliseconds to 30 seconds. Each control task is comprised of the I/O process point input scan, control scheme execution and an output scan. Two of the control tasks use predefined loops speeds of one-second and 100 milliseconds. The other three control tasks can have user-selectable loop speeds. Individual control sheets assigned to an available task coordinate the control execution loop time with the appropriate control function. Advanced diagnostics visible on Ovation HMI graphics indicate control task loop times for configured, average, worst case and standard deviation. Control Scheme OCR1100 functionality is defined by control sheets created from an extensive library of standard and advanced Ovation algorithms specifically designed for the power, water and wastewater industries. Control sheets provide the basis for executing, documenting and automatically creating control tuning diagrams used during commissioning and when adjusting control schemes. On average, the OCC100 controller can execute more than 1,000 control sheets. Sequence-of-Events Integral sequence-of-events processing capability is provided using Ovation I/O and standard controller software. With a resolution of one millisecond, the sequence-of-events subsystem records the sequence in which a set of user-defined digital input indications change state, providing a valuable troubleshooting and diagnostic tool for high-speed electrical systems. In addition to the higher resolution time tags, sequence-of-events points may be used in control schemes like any other I/O point, including limit checking and alarming. Alarm Processing The OCR1100 processes limits and alarms based on each process point’s database definition. These functions are performed regardless of whether the point is scanned for input to a control loop or for data acquisition separate from control functions. The alarm status of each point in the controller is updated with each scan. The status may indicate whether a point value has:  Exceeded the range of the sensor  Exceeded the user-defined limits  Changed state  Passed an incremental limit Alarm reporting can be delayed on a per-point basis by a user-specified period. When coupled with a workstation, the Ovation OCR1100 controller has the capability to report six independent alarm thresholds defined as:  Four high limits  User-defined high limit  Highest plus incremental limits  Four low limits  User-defined low limit  Lowest plus incremental limits The workstation can sort and display alarms based on a user-selected alarm significance level. Operator Interface Processing The Ovation controller performs all limit and alarm processing based on the database configuration for each point. However, Ovation HMI’s provide the capability to suspend these functions, as necessary, based on the process state or operator actions.