What is the role of feedback in a system? In information systems, feedback is information from the system that is used to make changes to input or processing activities.

Negative Voltage Feedback

• Voltage-series feedback.
• Voltage-shunt feedback.

Negative feedback can be achieved via four different forms. They differ in how the input and output impedances are changed….3.4: The Four Variants of Negative Feedback.

If either the output or some part of the output is returned to the input side and utilized as part of the system input, then it is known as feedback. Feedback plays an important role in order to improve the performance of the control systems.

Three basic types of control systems are available to executives: (1) output control, (2) behavioural control, and (3) clan control. Different organizations emphasize different types of control, but most organizations use a mix of all three types.

Elements of Process Control

• Controlled variable.
• Measured variable.
• Set Point.
• Deviation.
• Manipulated variable.
• Disturbances.

Many types of process control systems exist, including supervisory control and data acquisition (SCADA), programmable logic controllers (PLC), or distributed control systems (DCS), and they work to gather and transmit data obtained during the manufacturing process.

That’s why process control solutions are so important. Process control technology allows manufacturers to keep their operations running within specified limits and to set more precise limits to maximize profitability, ensure quality and prioritize safety.

Common process variables include – level, flow, temperature, density, PH(acidity or alkalinity), mass, conductivity etc. The SETPOINT is the target value of the process variable that is desired to be maintained. For example, if a process temperature needs to be kept within 5 °C of 100 °C, then the SETPOINT is 100 °C.

independent variable

Four commonly measured variables which affect chemical and physical processes are: pressure, temperature, level and flow.

A process variable, process value or process parameter is the current measured value of a particular part of a process which is being monitored or controlled. An example of this would be the temperature of a furnace. The set point is usually abbreviated to SP, and the process value is usually abbreviated to PV.

The ideal gas Law PV = nRT. Robert Boyle found PV = a constant. That is, the product of the pressure of a gas times the volume of a gas is a constant for a given sample of gas. In Boyle’s experiments the Temperature (T) did not change, nor did the number of moles (n) of gas present.

For a fixed mass of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional. Or Boyle’s law is a gas law, stating that the pressure and volume of a gas have an inverse relationship. If volume increases, then pressure decreases and vice versa, when the temperature is held constant.