Advanced Control Foundation : Batch and Continuous Processes — Interactive Source for Process Control

Wireless Control Foundation

Continuous and Discrete Control
for the Process Industry

Adding PIDPlus to Legacy Control Systems

Exercise

This workshop provides several exercises that are used to explore how PIDPlus functionality may be added to a control module in a legacy control system and then tested in a simulation environment. In this workshop it is assumed that the PID supports external reset.

Step 1: Open a module that contains a standard PID function block and examine the parameters of the PID block that are used to enable external reset capability and to connect the external reset input. Enable external reset in the PID.

Step 2: Identify the two composites that were added to the module that enable the PID to provide functionality that is equivalent to PIDPlus (for PI control). Examine the construction of these composite blocks.

Step 3: Examine the parameters and composite block that are used to simulate a first –order– plus– deadtime process and wireless communication.

Step 4: Enable wireless control in the composite, switch the PID to Auto and on a trend observe the response to changes in setpoint and process disturbances. Disable wireless control and on a trend observe the response for a change in setpoint and process disturbance.