Greetings djbillyd007 ...
disclaimer: I teach Allen-Bradley - and not the same brand of PLCs that you’re dealing with - but the material below should still fit right in with what you’re trying to do ...
one of the teaching approaches that I’ve found to be the most successful is to go through the plant’s existing programs and “pull out” the various parts (usually three or four rungs in a row) that seem to be giving the technicians the most problems in understanding ... then write a short lesson which focuses on those specific areas that are the most troublesome ...
basic idea: instead of teaching “how PLCs work” in general - this approach concentrates on “how the PLC works in OUR plant’s system” ... this helps you get the most bang-for-the-buck and it also lets the students know that the material that they’re learning will be IMPORTANT in their day-to-day jobs ... hint: never miss an opportunity to show them WHERE and HOW the skills that they’re studying will be used in the plant’s actual program ... this goes a LONG way toward keeping them motivated to master the material being covered ...
I use this same approach in the “custom designed” classes that I develop for individual customers ... the specifications for course W3808 are a good example of how detailed this approach can become ... you can find a copy at the bottom of
this page ...
notice that the course actually focuses on specific types of instructions (FBC, FLL, FSC, FAL, etc.) and drills right down to specific ladder files within the customer's program ... using an approach like this should help your new training project target exactly the material that your technicians need to cover ...
all of that having been said, I want to point out that “learning how PLCs work” in a general manner is GOOD STUFF and should NOT be neglected ... the point I’m trying to make is that with some “targeted” material you can more easily (and more quickly) show a definite return on your training investment ... please correct me if I’m wrong, but I’m assuming (gosh I hate that word) that you have $omeone up$tair$ who will want to see some tangible results from all of your training efforts ... if that’s the case, it’s going to be far better to tell them: “Now Joe is able to fix the conveyor by himself.” rather than: “Now Joe knows how to program a traffic signal.” ...
actually this same “targeted” approach has turned out to be one of the most successful marketing methods for my own classes ... once a plant maintenance manager has shown these types of tangible “dollars and cents” results to the people higher up his corporate totem pole, then it’s a lot easier for him to get authorization for even more training ...
on another topic, you might want to consider using an approach where some of your training system’s inputs and outputs are NOT already pre-wired when the students begin their projects ... you can get a feel for how my lab equipment is set up from the pictures
here and
here ... those terminal strips are EDUCATIONAL ...
the basic idea is that I don’t hand over a complete wiring diagram so that all the student has to do is “connect Point A to Point B” with a red wire ... instead I provide a separate schematic for the input module, a separate schematic for the output module, a separate schematic for the field devices, and a separate schematic for the power supply ... the student is expected to “make the circuits” and tie everything together ... many (most?) of them need help to get started, but the fact that they “need help” points out that these are skills that usually need honing ...
stop and think ... whenever a PLC-controlled system malfunctions, where is the problem USUALLY located? ... (A) in the field (wires, sensors, coils, etc.) - or (B) in the PLC’s ladder logic program? ... experience shows that about 99% of the time it’s NOT the PLC (bless its little heart) that’s keeping the plant from making money ...
and so my point is this:
do NOT neglect to show how the “real-world” devices in the field interact with the PLC and its program ... I am constantly amazed with how many PLC training programs completely disregard this IMPORTANT fact ... in most cases all of the “hands-on” lab equipment is totally pre-wired - and the course material covers ONLY what goes on inside the PLC ... there is seldom, if ever, any attempt to “tie it all together” so that the student learns to track down a problem all the way from ONE field device - THROUGH the ladder logic - and then on to ANOTHER field device that’s actually causing the malfunction ...
if all you cover is “what’s inside the PLC” then your training program is going to fail to address about 99% of the problems in your plant ... in my personal opinion, that’s why so many people consider PLC training to be a “waste of time and money” ... specifically, the PLC training that they’re used to getting does NOTHING to “tie the whole system together” so that a student learns the INPUTS - and the PLC - and the OUTPUTS - and how they all work together ... and more importantly - how to troubleshoot all the way from one end of the system to the other whenever things are NOT working correctly ...
anyway ... good luck with your program ... and please keep us posted ... some pictures would be nice - if you can arrange it ... we all love a good “train set” ...
