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Bob,
I went to Cotton Valley Wastewater Works to view four machines which had been supplied with a view to refurbishment and modernizing.
They were sludge/scum collectors, running on rails along a 100m tank, 30m across.
There was one central drive motor with chain drive to a single drive shaft from which chain drives drove the traction wheels. Obviously, they were known to "crab" and would derail, even falling into the tank! The traverse distance was controlled by a microswitch which incorporated a very complex watch type mechanism to count the distance. The control panel was bespoke, hard wired and relay controlled with big "Tardis" like lights, knobs and controls. I found that: a) I could get a replacement microswitch, but it cost 23,000 quid!;b)The guy who designed/built the control panel had retired about 25 years earlier!
Ripping everything out, installing a master and slave tracking motor and installing a PLC to control everything cost about 7000 quid!
So, I am in agreement with you! Modern electronics, off the shelf, plug and play is, in my mind, a wonder of the modern world.
Rgds.
Dave
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