The main components required to implement the use of a human machine interface in manufacturing are:

  • Sensors used to measure continuous and discrete process variables
  • Actuators used to drive continuous and discrete process parameters
  • Devices for analog to digital and digital to analog conversion
  • Input/output devices used for discrete data
Automation hardware components
Automation hardware components

The computer process control system is receiving input parameters (continuous and/ or discrete) and generating output variables (continuous and/ or discrete). In relations to that, sensors which are measuring variables can also be either continuous or discrete. The information is then sent to the control computer directly, in case the discrete sensors are retrieving digital values. Information is sent through analog to a digital converter (ADC) to control the computer in case of analog sensors which are measuring continuous variables, which can have any value that needs to be converted to digital data. The control computer then sends the control information to actuators. Discrete actuators are receiving data directly from control computer. Analog actuators are receiving data which is transformed with digital to analog converter (DAC).

Computer process control system
Computer process control system

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