Plant Control Systems

 

PLC

 

The Programmable Logic Controller (PLC) is what used in industry as the “brain” of the  control system. It connects to peripheral equipment in order to monitor the states of the peripherals via the input cards and actuates the different equipment for the peripherals that can be actuated via the output cards. This can happen via discreet on/off or a more real analog signal with a smooth transition from level to level.

 

SCADA

 

SCADA stands for Supervisory Control And Data Acquisition. This is a way for operators to interact with the the controls system equipment in a visual way. It is a replacement tool for the old plant mimics. SCADA allows the operator to see the PLC Inputs and Outputs in a way that represents the equipment so he /she knows what is happening in the plant from a central place.

 

If something is wrong in the plant then they will see that an alarm is raised and the operator would then determine if  the alarm needs action or just an acknowledgement.