Craig Spinharney
Member
- Join Date
- Apr 2005
- Posts
- 54
Instructional
When I was instructing PLC programmers for a living, I almost always used the traffic light or passenger elevator examples to get the beginners started.
As was mentioned above, we would start out with just 2-way controls. As the day and following days that week progressed, I would challenge them with more functionality...pedestrian crosswalk..."No Right Turn" lights (during pedestrian crossings)...left turn arrows...in ground presence sensors...a setting to allow for 4-way flashing Reds (after midnight) or an E-W Flashing Yellow/N-S Flashing Red....power-up sequence reset...
And all of this done using basic logic but later progressing using modular code so the student could see its advantages over what would otherwise become spaghetti code.
I had also created some logic that was part of everyone's project so that if the green light for both E/W AND N/S was on at the same time, the processor faulted. :angr:
We would use RSView32 (later FTViewSE standalone) and RSTestStand for the interfaces and RSEmulate for the processor. Originally done for the A-B PLC-5 later SLC500/MicroLogix and eventually Logix platform.
I had "ported" the class materials so it could be taught using ladder logic, structured text or SFCs. Because it was easy to relate to, the student got more out of it than if I had come up with some esoteric discrete process as the model to program for.
It's great watching students go from timid to "Hey teacher, my program detects if a dog takes a **** in the intersection!!!" in that 1 week.
When I was instructing PLC programmers for a living, I almost always used the traffic light or passenger elevator examples to get the beginners started.
As was mentioned above, we would start out with just 2-way controls. As the day and following days that week progressed, I would challenge them with more functionality...pedestrian crosswalk..."No Right Turn" lights (during pedestrian crossings)...left turn arrows...in ground presence sensors...a setting to allow for 4-way flashing Reds (after midnight) or an E-W Flashing Yellow/N-S Flashing Red....power-up sequence reset...
And all of this done using basic logic but later progressing using modular code so the student could see its advantages over what would otherwise become spaghetti code.
I had also created some logic that was part of everyone's project so that if the green light for both E/W AND N/S was on at the same time, the processor faulted. :angr:
We would use RSView32 (later FTViewSE standalone) and RSTestStand for the interfaces and RSEmulate for the processor. Originally done for the A-B PLC-5 later SLC500/MicroLogix and eventually Logix platform.
I had "ported" the class materials so it could be taught using ladder logic, structured text or SFCs. Because it was easy to relate to, the student got more out of it than if I had come up with some esoteric discrete process as the model to program for.
It's great watching students go from timid to "Hey teacher, my program detects if a dog takes a **** in the intersection!!!" in that 1 week.
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