The leading PLC providers include •Rockwell Automation : Allen Bradley (Micrologix, SLC, PLC, Control Logix) •Siemens ( S7 200, S7 300 , S7 400) •Schneider Electric : Modicon ( Nano, Micro, Premium, Quantum) •GE : Versa, Series 90-30, 90-70 •Messung : Nextgen