ON/OFF signals - Buttons and lamps


Buttons and signal lamps are using simple digital inputs and outputs i.e. ON/OFF signals. Digital inputs and outputs signals are most basic and also most common signal types on PLC controllers. With input signals controller can acquire information from sensors or human operators. For example contact sensors or contactless proximity sensors inform controller that some object is touched or is apparent in range. Based on this data PLC can generate output signal to stop the motor, light up the signal lamp etc. Simple buttons act as digital inputs and enables to provide human interaction to machine.


Learning outcomes

After completing the topic student shall be able to…   

  • Handle digital inputs and outputs,

  • Use and change parameters in program blocks,

  • Set and reset bits,

  • Use timers and counters in program,

  • Connect digital inputs and outputs in a proper way.

Suggested readings

  1. General topic: PROGRAMMABLE LOGIC CONTROLLER (PLC), https://www.myodesie.com/wiki/index/returnEntry/id/2962

  2. Video: PLC What it is and how it works, https://youtu.be/rh5DfK2JWmA