How Do You Know When to Upgrade Your Control System?
There are many ways to approach this question, but the best way is by asking yourself some questions ... five of them.
It always amazes me when I walk into a “modern” factory and see equipment with control systems from the 1970s.
To put this in perspective, Allen-Bradley’s PLC-2 family was released in 1978. It would be another year before you could fax a document or listen to the Village People on your Walkman.
General Electric’s Series 6 system would be introduced in 1981, the same year as Microsoft Disk Operating System (MS-DOS) – one year before the Commodore 64. And yet,
there are many of these and other antiquated systems still in use today.
Recently, I turned on my Apple II, put the phone headset in its cradle and dialed into CompuServe.
Why did I do this? Because I needed to find information on a programmable logic controller (PLC) first introduced in 1978, and I was hoping that someone on one of CompuServe’s forums could help me.
So just what was a PLC capable of in 1978? Not much. The basic PLC handled analog and digital inputs and outputs, and little else.
Forget about communications to the outside world, data collection, integrated motion, and many of the modern software and hardware functionality now prevalent on most controller platforms of today.
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