Working with Controllers

Course Number: 781

This course describes the purposes and kinds of controllers and their relationship to other components in process control systems. It explains the concepts of current-, position-, and time-proportioning control and compares the operation of several kinds of controllers. It describes the operation of proportional, integral, and derivative modes, and discusses tuning procedures for each. Also covered are cascade, feedforward, ratio, and auctioneering control systems and other operations. Finally, it describes ways to eliminate or reduce controller problems.

Recommended Contact Hours - 8

Chapter 1: Introduction to Controls

Topics: Process dynamics; Current, position, and time proportioning; Controller modes, actions, terminology, and options; Loop accuracy

Learning Objectives:

• Describe the kinds of controllers most often used in industrial applications.
• Discuss six important problems of process dynamics that controllers must overcome.
• Compare the actions of current proportioning, position proportioning, and time proportioning.
• Name four kinds of controller alarms.
• Discuss the importance of safety in control loops.

Chapter 2: Controller Operations

Topics: Automatic/manual control; Range and span; Direct-, reverse-acting, on/off, and proportional controllers; Current, time, and position-proportioning control; Control strategies

Learning Objectives:

• Explain why automatic/manual control is necessary.
• Explain how on/off controllers work and discuss the difference between on/off and proportional controllers.
• Describe a basic controller tuning process.
• Describe current-, time-, and position-proportioning controllers and name possible uses for each.
• Explain how split control works.

Chapter 3: Controller Modes and Tuning

Topics: Proportional mode; Offset; Integral mode (reset); Derivative mode (rate); Single, two, and three mode controllers; Loop tuning; Step-change response

Learning Objectives:

• Describe the effect of the proportional, integral, and derivative modes on a controller's response to process changes.
• Discuss proper uses for the proportional, integral, and derivative modes.
• Explain how the proportional, integral, and derivative modes affect the tuning of a controller.
• Describe the procedure for tuning a controller by the step-change response method.

Chapter 4: Special Controller Applications and Options

Topics: Cascade, feedforward, ratio, and auctioneering control; Hardware options; Remote setpoint; Auxiliary outputs; Indicators; Limits and alarms

Learning Objectives:

• Compare cascade, feedforward, ratio, and auctioneering control strategies.
• Describe three optional features used with auto/manual controllers.
• Discuss the use of remote setpoint, auxiliary outputs, and several kinds of indicators as hardware options for controllers.
• Explain how input signal conditioning, anti-reset windup, adaptive gain, error-squared calculation, and setpoint/output ramp and clamp affect controller operation.
• Discuss the use of limit and alarm options available for controllers.

Chapter 5: Maintaining Controller Systems

Topics: Preventing problems; Electrical noise and suppression; Regulating power; Electrical coupling; Temperature variation; Troubleshooting

Learning Objectives:

• Describe five ways of suppressing electrical noise.
• Discuss the effects of an inadequate power supply and explain how to regulate it.
• Describe ways to avoid the harmful effects of electrical coupling.
• Explain how temperature variations affect controllers.
• Describe the kinds of equipment and proper connections needed to test controllers.
• Discuss elements of effective controller maintenance and troubleshooting.