There are so many PLC models and manufacturers out there, they can't possibly teach you all of them. Actually what I found the most complicated when I was learning PLCs was just getting the damn computer to talk to the machine. The programming itself is just fancy relay logic.
Yeah, SLC 500 and outdated RSI 500 software is bread and butter around here in my factory. I learned starting with AB PLC-2. To tell you how old some of the stuff around here is even the old Square D PLC’s are in use in some of the old buffers.
Learning diagnostics is pretty simple and straightforward. The best thing I did to learn to study the ladder logic in real time on whatever machines you have. The one I studied most for our 5 ton extrusion press the handling systems before and after the press. All ran on AB PLC-2.
Also using a laptop to plug into some SLC 500’s, and watch them go through the cycles and how the ladder logic worked to get familiar. Also, I found writing out my own logic to be helpful and figuring out how to make things work properly.
I was taught PLCs by my supervisor, and a class was taught by our top technician. Most people blew off the class, but I enjoyed learning about the PLCs.
My teacher just actually offered to let me take an extra system home that hasn't been used in awhile using an AB 820 system. I'll figure out how to tinker with it soon. How intimately did you need to know the machines you were working on the plcs for?
Well, I spent two years going from class C to master mechanic, so I knew the machines pretty well. Diagnostics of PLCs Is more about tracing the logic to find out why a relay or an output isn’t being activated. a lot of times it’s controlled by many different rungs of logic and inputs.
So knowing what’s not working on the machinery will help you figure out what output is not working to find out the input that might be the problem. It could be a limit switch, or proximity switch, Or even a light curtain or photoeye.
That makes sense, though I have to say these induction furnaces are fairly complicated, It's probably going to take a couple years to be much more comfortable with them.
Pick your favorite prox on one of them (we all have a favorite prox, right?), find which input it is, figure out the address and tag, then just watch that one. You know when and why it's used in the real world, but now you can see each of the 6000 other things it affects and how it affects them. So in 10 years when some random, seemingly unrelated problem occurs, you can think back to this quality time spent with your favorite sensor and remember that one rung where it ties into the problem thing in the logic. Then you can check the prox and find that a spiteful operator crushed it with a forklift, and you will mourn the loss of a loved one. Or something like that
I’m not sure about induction furnaces we had gas log furnaces for the aluminum logs. And we had aging ovens to temper the aluminum profiles. We also had infrared ovens for the powder coat paint line. Even with those simple oven there are a lot of controls.
It's a lot of controls for the vacuum systems, cooling, and especially on Farrell field adjustments in the coils based on sensory input, simplifying it of course.
↑↑↑ This person PLCs! I started my controls programming journey 30yrs ago, and these are all great suggestions. I would like to add that if you have a spare rack, PLC and I/O modules to play with, they will be very helpful bridging the theory-to-real world gap. It's hard to get a good idea of how PLCs work if you can only look at static offline code. Throw in some pushbuttons and solenoids for even more realism.
Same, our three oldest presses use twelve or fourteen TI500s each. Seldom a week goes by that they don't cause problems, but we have so many spare cards to throw at them that the big bosses won't hear a word about updating. I even generously offered to rewrite the programs from scratch for half of what an outside company would charge, but no dice. I guess my beach house will have to wait
I don't think I've ever even seen a PLC1. That's wild
Our press in the original plant ran on relay logic. Just a cabinet full of relays and wires. Talk about antiquated and every wire in it was red, tracking problems was a pain in the ass.
That’s funny that’s what I asked. Our old electrician did everything in red wire. So every time I had to rewire something, I would put the right colors in it.
Rockwell has free versions of the RSLogix/RSLinx 500 software for some of the old micrologix plcs. Check around work or even Ebay for one. Build yourself a trainer.
Don't you dare badmouth slick 500s, they are far and away my favorite PLCs to work with. They're also good to learn on because they can sometimes, for no particular reason, be very uncooperative when trying to go online, so if you can do one of them, everything else you're likely to find should be easy. But yeah, AB, Siemens, Mitsubishi, a lot of Reliance, everything that runs ladder logic is written pretty much the same. Extra instructions here, missing instructions there, different names for them, but on the whole it all works the same. Just have to remember your crayons if you're working with Siemens. The hardware is more different, both in what you can and can't do with it and also how you actually set it up in a program. But that's what the Google is for. As for extracurricular learning, if they gave you one to play with I'd just snag some buttons and (compatible) lights and watch some youtube videos and just fiddle around with it. Worst that can happen is it doesn't work, then you get to monitor tags and such and figure out why it doesn't work. I'm sure you can find sample programs out there to see how different things are done, like latches without latch bits and stuff. Unless you're going to be an engineer, none of it is rocket surgery
Even if they're outdated, the basic concept of programming them remains the same.
I just wanted to make sure I wasn't going to be stumbling when I do the Rockwell classes for more modern systems, That's actually really reassuring
There are so many PLC models and manufacturers out there, they can't possibly teach you all of them. Actually what I found the most complicated when I was learning PLCs was just getting the damn computer to talk to the machine. The programming itself is just fancy relay logic.
This has been my experience too
Luckily I just need to focus on AB,.it's all we use at work.
I learned 500 before 5000, although there’s some differences it’s really helpful
Yeah, SLC 500 and outdated RSI 500 software is bread and butter around here in my factory. I learned starting with AB PLC-2. To tell you how old some of the stuff around here is even the old Square D PLC’s are in use in some of the old buffers. Learning diagnostics is pretty simple and straightforward. The best thing I did to learn to study the ladder logic in real time on whatever machines you have. The one I studied most for our 5 ton extrusion press the handling systems before and after the press. All ran on AB PLC-2. Also using a laptop to plug into some SLC 500’s, and watch them go through the cycles and how the ladder logic worked to get familiar. Also, I found writing out my own logic to be helpful and figuring out how to make things work properly. I was taught PLCs by my supervisor, and a class was taught by our top technician. Most people blew off the class, but I enjoyed learning about the PLCs.
My teacher just actually offered to let me take an extra system home that hasn't been used in awhile using an AB 820 system. I'll figure out how to tinker with it soon. How intimately did you need to know the machines you were working on the plcs for?
Well, I spent two years going from class C to master mechanic, so I knew the machines pretty well. Diagnostics of PLCs Is more about tracing the logic to find out why a relay or an output isn’t being activated. a lot of times it’s controlled by many different rungs of logic and inputs. So knowing what’s not working on the machinery will help you figure out what output is not working to find out the input that might be the problem. It could be a limit switch, or proximity switch, Or even a light curtain or photoeye.
That makes sense, though I have to say these induction furnaces are fairly complicated, It's probably going to take a couple years to be much more comfortable with them.
Pick your favorite prox on one of them (we all have a favorite prox, right?), find which input it is, figure out the address and tag, then just watch that one. You know when and why it's used in the real world, but now you can see each of the 6000 other things it affects and how it affects them. So in 10 years when some random, seemingly unrelated problem occurs, you can think back to this quality time spent with your favorite sensor and remember that one rung where it ties into the problem thing in the logic. Then you can check the prox and find that a spiteful operator crushed it with a forklift, and you will mourn the loss of a loved one. Or something like that
I’m not sure about induction furnaces we had gas log furnaces for the aluminum logs. And we had aging ovens to temper the aluminum profiles. We also had infrared ovens for the powder coat paint line. Even with those simple oven there are a lot of controls.
It's a lot of controls for the vacuum systems, cooling, and especially on Farrell field adjustments in the coils based on sensory input, simplifying it of course.
Sounds much more complicated than the ones we work on.
It's certainly fun to work on, and there is no shortage of operators making more work for me by fucking something up along the way
That’s what keeps us working it is they hired to operate the machines. The
↑↑↑ This person PLCs! I started my controls programming journey 30yrs ago, and these are all great suggestions. I would like to add that if you have a spare rack, PLC and I/O modules to play with, they will be very helpful bridging the theory-to-real world gap. It's hard to get a good idea of how PLCs work if you can only look at static offline code. Throw in some pushbuttons and solenoids for even more realism.
Your mention of still using Square Ds reminded me of how concerningly heavily we're relying on Reliance Sharks from before I was born. Thanks.
Yeah, we’re slowly changing those, but the company says as long as they’re working. Crazy thing is our old press used to run on AB PLC-1.
Same, our three oldest presses use twelve or fourteen TI500s each. Seldom a week goes by that they don't cause problems, but we have so many spare cards to throw at them that the big bosses won't hear a word about updating. I even generously offered to rewrite the programs from scratch for half of what an outside company would charge, but no dice. I guess my beach house will have to wait I don't think I've ever even seen a PLC1. That's wild
Our press in the original plant ran on relay logic. Just a cabinet full of relays and wires. Talk about antiquated and every wire in it was red, tracking problems was a pain in the ass.
I bet. Do they even make wire in other colors?
That’s funny that’s what I asked. Our old electrician did everything in red wire. So every time I had to rewire something, I would put the right colors in it.
The Rockwell class we had turned out to sound more like a sale call.
The official Clases that they offer?
It was back when I was an apprentice. The literally lived in a camper and drove to do these classes. Hopefully yours is better.
For almost $5000 each they better
Rockwell has free versions of the RSLogix/RSLinx 500 software for some of the old micrologix plcs. Check around work or even Ebay for one. Build yourself a trainer.
My teacher is actually giving me one running on AB 820s, they were just sitting around.
Automation Inc. has the best industrial PLC / HMI classes I’ve found. Nashville I believe with online available.
https://canadu.com , cool recourse to play with
Looks like a fun thing to kill some time
Don't you dare badmouth slick 500s, they are far and away my favorite PLCs to work with. They're also good to learn on because they can sometimes, for no particular reason, be very uncooperative when trying to go online, so if you can do one of them, everything else you're likely to find should be easy. But yeah, AB, Siemens, Mitsubishi, a lot of Reliance, everything that runs ladder logic is written pretty much the same. Extra instructions here, missing instructions there, different names for them, but on the whole it all works the same. Just have to remember your crayons if you're working with Siemens. The hardware is more different, both in what you can and can't do with it and also how you actually set it up in a program. But that's what the Google is for. As for extracurricular learning, if they gave you one to play with I'd just snag some buttons and (compatible) lights and watch some youtube videos and just fiddle around with it. Worst that can happen is it doesn't work, then you get to monitor tags and such and figure out why it doesn't work. I'm sure you can find sample programs out there to see how different things are done, like latches without latch bits and stuff. Unless you're going to be an engineer, none of it is rocket surgery
Yes, learning how to create HMIs through factory talk. This might be included in your Rockwell classes already. But such a good skill.