On 7/18/2011 12:17 PM, Jon Elson wrote: > andy pugh wrote: > >> http://www.emi-mec.eu/autosprinte/progcontrol/index.php5 >> >> (prompted by >> http://cgi.ebay.co.uk/Emi-Mec-Auto-Sprint-Series-E-Emi-mec-lathe-/180693575715 >> ) >> >> > Oh MY! It looks like a move back to the 1950's! GROAN! > > Jon > > Allen Bradley had a controller that was their precursor to the PLC that used some sort of plug type grid array so it could be programmed. I saw one in 1977 at a GM plant. It had been ripped it out a few years before. It was not well liked. It was call the Allen Bradley PMC (Programmable Matrix Controller)
An interesting time line of PLC development: http://www.plcdev.com/plc_timeline I was a coop engineering student at a car plant that was about 1000 feet from where Richard (Dick) Morley installed the first PDP based "PLC". Years ago I had an long email exchange with Dick Morley who is attributed as being the inventor of the PLC. How things change: The car plant were I cooped is now a big GM owned warehouse. That car plant was about 1000 feet from the Hydramatic transmission plant where Dick Morley installed his first PDP based "PLC". The 5 million square foot Hydramatic plant was shut down by GM last year, but I heard that they have a couple hundred people working there again now... they must have plenty of space! Most of the production was moved to the much smaller GM Toledo Transmission plant. Dave ------------------------------------------------------------------------------ Storage Efficiency Calculator This modeling tool is based on patent-pending intellectual property that has been used successfully in hundreds of IBM storage optimization engage- ments, worldwide. Store less, Store more with what you own, Move data to the right place. Try It Now! http://www.accelacomm.com/jaw/sfnl/114/51427378/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
