An engineer is responsible for the control design of a new plant. The DeltaV control system will not be shipped for another month, but he has installed DeltaV Simulate on his computer. One loop that is critical to plant operations uses a feedforward signal from a feed stream that is not used for some products. Under the condition of no flow, the input signal can have a BAD status. It is important in his design of the control system to understand how the PID behaves under this condition.
To learn more about how the PID operates under such a condition, the engineer assigns the associated control module to his computer, downloads, and then, using Control Studio's online view, examines the PID and feedforward signal provided by an AI block. Utilizing the SIMULATE parameter of the input blocks to the PID, he establishes a normal operating condition. Then, by changing the SIMULATE parameter status of the feedforward input to BAD and back to GOOD, he observes that the operation of the PID is not disrupted by the status going BAD. Knowing that the DeltaV PID addresses this situation, the engineer is able to finalize the design of this critical control loop.