Allen-Bradley (Rockwell) ControlLogix 5000 PLC System

A modern PLC manufactured by Allen-Bradley (Rockwell) is  this  ControlLogix  5000 system, shown in this photograph used to control a cereal manufacturing process.  The modular design of the ControlLogix 5000 system follows the more traditional scheme of individual cards plugged into a rack of fixed size:

Article from Lessons In Industrial Instrumentation by Tony R. Kuphaldt – under the terms and conditions of the Creative Commons Attribution 4.0 International Public License