Which statement best defines feed-forward proportional control?

Which statement best defines feed-forward proportional control?

• A. Measures the output of the process and reacts backwards to adjust the operation of the piece of equipment.
• B. Involves variable-speed drives with no feedback.
• C. Measures a variable and adjusts the equipment proportionally.
• D. Single-phase are only used in fractional horsepower sizes.

Answer: (C)

Feed-forward proportional control acts ahead of the process by using a measured disturbance or input variable to drive the actuator in direct proportion to that measurement, before the process output has a chance to deviate. This proactive adjustment helps keep the system on track without waiting for a change to show up in the output, which is what you’d see in pure feedback control. The description that best fits this approach is: measures a variable and adjusts the equipment proportionally. In contrast, describing the control as measuring the process output and reacting to it reflects feedback control, and open-loop operation means no measurement or disturbance compensation at all. The option about motor phase or horsepower is unrelated to the control strategy.

Feed-forward proportional control acts ahead of the process by using a measured disturbance or input variable to drive the actuator in direct proportion to that measurement, before the process output has a chance to deviate. This proactive adjustment helps keep the system on track without waiting for a change to show up in the output, which is what you’d see in pure feedback control. The description that best fits this approach is: measures a variable and adjusts the equipment proportionally. In contrast, describing the control as measuring the process output and reacting to it reflects feedback control, and open-loop operation means no measurement or disturbance compensation at all. The option about motor phase or horsepower is unrelated to the control strategy.