Ronnie Sullivan
Member
The title might be a bit grand but I came across a program written over 30 years ago by the factory engineer (long since retired) and marveled at his out of the box thinking.
The machine was a sort of storage and retrieval system.
Freshly made bricks were transported by a overhead crane into a drying warehouse and stacked in rows.
It kept tabs on when bricks and where bricks were dropped and which ones were ready to be brought out and packaged.
All this was done automatically and it hadn't faulted in all those years.
At some point, they needed a method to retrieve rows of bricks manually.
The system didn't have an HMI so they had to guide the crane by hand
to the appropriate row (there are hundreds of rows) by eyesight and get them that way.
The engineer solved the problem by fitting a metal number keypad
But this keypad was not designed for this. I think it must have come off a door entry system or something.- He had butchered it so that each number had a seperate input to a seperate plc.
When they pressed a number, the separate plc pulsed an output corresponding to the number, into the main plc's input.
A green light came on to say it was ready for the next number and when they had done they pressed send or recieve
And the crane set off in auto mode to the correct row.
Nice.
I am in the process of retro-fitting a new plc and of course a shiny new HMI
The machine was a sort of storage and retrieval system.
Freshly made bricks were transported by a overhead crane into a drying warehouse and stacked in rows.
It kept tabs on when bricks and where bricks were dropped and which ones were ready to be brought out and packaged.
All this was done automatically and it hadn't faulted in all those years.
At some point, they needed a method to retrieve rows of bricks manually.
The system didn't have an HMI so they had to guide the crane by hand
to the appropriate row (there are hundreds of rows) by eyesight and get them that way.
The engineer solved the problem by fitting a metal number keypad
But this keypad was not designed for this. I think it must have come off a door entry system or something.- He had butchered it so that each number had a seperate input to a seperate plc.
When they pressed a number, the separate plc pulsed an output corresponding to the number, into the main plc's input.
A green light came on to say it was ready for the next number and when they had done they pressed send or recieve
And the crane set off in auto mode to the correct row.
Nice.
I am in the process of retro-fitting a new plc and of course a shiny new HMI