How to Build a PLC Training Kit Students Learn From: Real Terminals, Real E-Stops, Clear Diagrams

How's it going, everyone? Vlad here, and welcome back to the conversation around the most upvoted topics in our industry. Again, I wanted to apologize. I took a little break. With all the conferences and the client site visits that I had previously, I was unfortunately unable to make this content. That being said, I am very excited to look back at some of the past weeks, look at the upvoted sections, and give you some of my feedback.

So today, we're going to do the exact same format as we've done in the past. Of course, if you disagree, if you have some other opinions, if you have some other questions, make sure to leave me a comment. It is easiest to reach me either on the YouTube channel or on LinkedIn, where, once again, you can either message me privately or leave me a comment on the content

Logix Designer laptop meme: why engineering software needs real RAM

All right, so our first piece of content, or I guess comment from the username Archangelou is basically a meme

So he says, "My computer when I open a project on Logix Designer," and of course, the joke here is that a bunch of CPUs immediately need to start functioning. I'll spare you watching the entire video. You can find it on the subreddit. Now, the joke of course, and I will switch the camera to myself is that many of us that have been in the industry long enough know that you need a fairly beefy laptop.

So if you ever seen my machine in the field, you will see that I have a seventeen-inch laptop that is-- it's basically a gaming laptop with an embedded graphics card with thirty-two gigs of RAM. And the reason for that, of course, is that you need a lot of power to be able to run Logix Designer, which is the Rockwell IDE either RSLogix or Studio of course for those who are unfamiliar, maybe you come from a different part of the world.

And the joke goes deeper than that, right? So I will expand a bit on my personal experience with, some of these, I would say, discussions and if you will, with IT/OT teams. Number one, when you work in control systems, especially if you're running PLC IDEs, like I've mentioned, whether that's Studio or even TIA Portal, these are fairly sophisticated pieces of engineering software, so they require a lot of RAM as well as CPU or processing power.

So the joke for me is that I've always traveled with a fairly large power supply as well. It's in my backpack. But typically, the business people, if you will, at least earlier in my career, or the marketing people, would make fun of the laptop that I need to carry around, which again, is substantially heavy but is also very loud.

So if you ever join some of my meetings, especially in person, you will hear the fan. As soon as I turn on any engineering software, you will hear the fan spin quite extensively. Now, of course, it doesn't bother me because I either work in noisy environments or have headphones on, so it's not-- it is a non-issue.

Where it is a problem, again, for those who are maybe new to the field, is when IT or the department that's giving out the laptops doesn't understand some of these requirements for, Again, I can obviously spend a lot of time to be giving the reasons that I think that is. But ultimately, they give you a laptop with four gigs of RAM and a ten-year-old CPU.

It's a thin HP laptop that cannot run Logix Designer or takes half an hour to open Logix Designer, and it is a big pain for people that work in control systems. I have heard of many employers making that same mistake. So basically, they're saving a little bit of capital on the laptop, but they are paying a lot of capital in the time wasted on the engineering side.

So again, this is a very common meme in our industry because it is true, it does consume a lot of processing power to be able to run some of those tools.

Thin laptops vs a virtualized engineering workstation on Proxmox

There are other options. Again, if you do want to go the thin laptop route, you can install virtualization. You can create virtual machines either in Windows Server or in Proxmox, and then be able to provide remote access to an engineering workstation that will run Studio and RSLogix 5000 with the engineer remoting into that station with a very thin machine.

So that is definitely possible and a workaround that I have seen many employers implement successfully and some not so successfully, again, depending on your setup.

Hi, my name is Vladimir Romanov. I am the founder of Joltek as well as SolisPLC. With a background in electrical engineering and an MBA, and over a decade of experience leading projects in manufacturing and industrial automation, I help engineers, managers, and manufacturers make smarter technical and business decisions, modernize their operations, and build stronger careers.

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Mitsubishi PLC trainer review for an engineering university

The second question is around a training kit. And as many of you know, I have worked quite extensively on training materials. I have provided full courses on SolisPLC. I have built my own training kits. So I do have a lot of opinions when it comes to building a training kit, whether that's for students who are currently studying engineering or professionals who are looking to basically advance their career in industrial automation across the entire stack, whether that's at the field level all the way up to SCADA and MES systems

And so this comment, or I guess this photo, comes from the user or-ordinaryjeweler569. And they say, "I have built this training kit for an engineering university. Mitsubishi Electric Corporation sponsored this kit, and yesterday we hand over this kit." So let's take a look. Again, it looks like we can zoom in, so this is really nice.

So Mitsubishi PLC Trainer, sponsored by Mitsubishi Electric Corporation through Satsuyo Aztec Corporation and Progressive Engineering Corporation. So we have a couple of things on the kit. Let's start to the left. We have a power supply, which I would assume either receives two twenty or one ten. Uh, let's see here.

It's not entirely clear. Uh, we have some circuit breakers here, six amps. That is excellent. We have a Ethernet switch. What I would assume is unmanaged. Odot is a brand I've heard of multiple times. They've reached out to try and sell me hardware. Not a huge fan based on their practices, but again, maybe their Ethernet-based hardware is okay.

We have the PLC, right? So this is the Mitsubishi Electric PLC that we're working with. I'm not overly familiar with all of their lines. I'm assuming that this is the equivalent based on the form factor alone of a MicroLogix type of a PLC, where you have digital I/O, as well as maybe some analog.

Again, we'd have to look up the part number to be sure. We have an HMI. Once again, this is the Mitsubishi Electric HMI. Very interesting. We have next to that a VFD. Let's see here. So D800. I'm sure it's very easy to look up the part number and be able to see what's the VFD doing right now. Obviously, it's, uh, set to zero, so it's not running.

We then have a stack light of three lights that's perfectly fine.

Banana plugs, color codes, and why terminals matter

We have a bunch of distribution blocks. So I'm not a huge fan of these banana plugs. I think that banana plugs... And I've used them in university for some basic circuit simulation. I would love to see normal terminals inside of the training kits because that is ultimately what you will see in the field.

So for me, this is a huge missed opportunity to allow the students to actually land the cables, and I think it just-- it looks very tacky, at least to me. The other comment is, of course, the color scheme. I am unclear as to why the twenty-four volts DC is yellow and zero volts DC is blue. Maybe this is some kind of a different scheme in Asia But in any case, that is what we've got.

We have a variety of different, I would suppose, inputs and outputs. So we have, again, this strange yellow and blue scheme going on. We have a couple of analog, , inputs, right? So this is our analog input, zero to ten volts DC on the input side as well as the output side. We have a common. So it looks like we have two inputs and we have one output.

Again, it's probably going to be a challenge to locate those on the actual PLC, but let's assume that they are all there. , What else do we have? So we have VFD control terminal. So we have... Interesting. This is not the wiring that I would expect. So I'm not even sure what these are. Two, five, ten. So I guess maybe these are the pins from which the, , drive is coming in, and these can be connected to some IO, SDF, SDR, RL, SD.

Interesting. So once again, not entirely sure as to what these terminals represent. It looks like there's plenty of room to write out the functions of each one of these inputs or outputs. We have RS485 on the VFD. Once again, I see a normal USB plug, so I would assume if you wanted to configure this, you could simply plug in via USB.

Maybe you need to tie this into the PLC to be able to speak w- to it, but unclear. , Tower lamp terminal, red, yellow, green, and buzzer. So it looks like there-- Oh, there is the buzzer at the bottom. So again, these are probably, I would say, digital inputs, right? So if you tie your twenty-four volts to any one of these, it would work.

Of course, you need the common as well. Let's see here. What else do we have? We have miniature relays. , Again, we have the diagram. It would be nice to have some kind of a better drawing, I would say, on these face plates. It's not that, , intuitive, at least I would say, for the students, and you have a ton of real estate, so you could have different diagrams next to the relays.

Of course, they can be replaced and changed out, so maybe that's why they decided not to have this. We have some push buttons, an emergency switch, so push button one again, I'm assuming that the common is related through this push button. We don't know if this normally open, normally closed. I would assume only based by the color that this is normally closed, this is normally open, normally closed, normally open.

Again, it-- there's a lot of space for the diagrams, so that should be, I would say, again, drawn out a little bit better.

A single channel E-stop is not an E-stop

The emergency stop, this is very concerning. So normally, E-stops are going to be, , your dual channel safety circuits. It seems to me if there's only one line that this is not an actual E-stop, it's just the form factor of an E-stop, but it really is a normal push button.

We have a switch which is a three-way switch. Again, it looks like it maybe connects the common to either manual or auto. This diagram is really terrible because manual and auto are connected via the switch, so this is not very representative of at least a toggle switch that I have seen in the field.

Unclear what it does. We have some indicator lamps. Again, we have common. I would assume that if you have common and then you apply twenty-four volts DC at either one of these, it will come on. We have the motor output, which probably goes to... Yes, we saw the motors on the bench So we have a three-wire motor layout, so again, this makes perfect sense.

It's not clear to me, at least in this setup, if the VFD underneath is wired to this motor output, or I need to basically bring the three phases. Again, not sure which ones. It's probably ABC, right? So A lands in this terminal, B lands in this terminal, and C lands in this terminal. But anyways, let's see here.

So we have the relays. We have a potentiometer, which I think is a good idea. You can create the analog values that you're looking for as the inputs by using the potentiometer. Of course if it's a single value, maybe you can use that as a divider. But to be determined. We have a DC voltmeter. You can measure an analog signal.

We have a push/pull solenoid and proximity sensor. So I'm assuming that once this actuates, it's going to block off the proximity sensor. It-- This is a very interesting setup. I'm not sure why you would need this, but maybe you can play with these solenoids. And from what I have seen on AliExpress, at least, this is a very cheap part that you can buy for maybe five to ten dollars.

And you can, again, if you apply twenty-four volts, it's going to extend the solenoid and the proximity switch, in this case, is going to pick up the the reading of the position. We have a photo sensor, and we have, of course, a limit switch, which when pressed, is going to be typically closed, and this could be tied to some wiring on the bottom.

How I would design a PLC training kit

It is a, it is an interesting PLC trainer. I think that there's a lot of improvements that could be made. I think it can also be much more compact. And not that it needs to be more compact, but I think there's just an opportunity for that. I think that there's just a lot going on for where the outputs are broken out, where you normally would see terminals, and I would want the students to practice with the terminals.

I think that there's a lot of push buttons and other devices that could just be left out in the field for specific exercises. I think that once you've wired some of these lights once, maybe twice, maybe three times, in my experience, it becomes old very quick. So I m- don't necessarily want to have that as a permanent attachment to the kit.

I typically want the major devices as a single kit, and everything that's outside of that comes in at terminal so that you can use the main kit for a variety of different exercises. But again, this is something that you learn with experience. I would assume that this is the first time this person is building this kit, and so that's the approach that they took.

If they-- obviously, if the university's happy as well as with the training materials, more power to them

Capstone panel review: PLC and ESP32 two tank system

All right. The next question/comment is a panel review. There's quite a few panels that get upvoted on the subreddit, and of course, there's a lot of questions, there's a lot of comments. This is an interesting one, right? Because it is not a full production panel, but rather a capstone project So this comes from the username Honey41Badger.

First panel for my capstone project. And let's see here. He says, "Hello everyone. I'm doing my capstone project using a PLC and an ESP32 for a two-tank transfer system. I would like some tips or criticism for the design. I'm planning to number the wires in a few days and remove the breadboard and move to an e-stop after I test the whole machine.

Any advice?" So let's take a look if we can click in. Nice. We should be able to zoom in and discuss the panel. So first and foremost, let's start from, again, top to bottom and of course left to right. We do have a power supply. This is some kind of a Chinese brand, as we can see by the name. IRAU Electric model DR6024, input 100 to 240 VAC, output 24 volts DC.

Very standard. Again, this is something you typically need. There's some unconnected ground, which again could be a red flag, of course, if it goes into production. So would recommend putting in the ground. We are switching only one leg, which I would hope is the, uh, phase that's coming in. That is acceptable.

It is not ideal, but it's fine. Next, we have some terminals. Again, this is 209, so I'm assuming that it's coming from the... No. So this is not 24 volts. So there's some strange color schemes going on. Maybe this is just the phase, but for whatever reason, one side is red, the other side is white. I would recommend having the same color scheme.

Again, obviously, if you built the panel, you know exactly what it is, but this is not following a standard that I have seen. We do have some wires coming down into the other terminal blocks. Again, terminal blocks are good, right? There's definitely strange labels. Maybe there's a different scheme that, than I'm expecting.

Arduino Opta and doubled up relays

There's some numbers, which is okay we have the Arduino Opta. Again, I have some reservations as to the functionality of the Opta. I understand why this is being used in the capstone project, especially for a student. As you will find, if you haven't seen some of my oldest videos, I have done a ton of Arduino programming.

I have a lot of different tutorials on this channel. And of course, the Opta is the industrialized, if you will, Arduino, which allows you to run the Arduino IDE, but also run a completely separate IDE for programming the way you would do with PLCs. What this person has done is obviously unknown because all we're looking at is the hardware, but it would be interesting to hear from the original poster if they're using the Arduino IDE in C/C++, or if they're using the Opta programming environment.

So we have some cables. Again, it's very difficult to say what exactly we're looking at in this case. I'm assuming it's some of the IO. We have a set of relays, and from what I remember, this is just a voltage meter. Maybe it's, it's a regulator and it's changing the voltage down to probably power the ESP to which we're going to get to in just a moment.

We have multiple relays, right? So we're switching four different solid-state relays. These are very common boards to see, especially in hobbyist electronics. So you will notice that You can go on AliExpress and buy these for a couple of dollars. There's going to be some configurations using these basically terminals, and you can adjust the functionality of the relay.

But you can use this to drive larger loads, and I'm not sure if-- So we have already relays on the Opta, at least on this version, we have 10 amp outputs. So I'm not sure if there's even a need for these relays, but for whatever reason, they've decided to go that route. Again, maybe that's part of their electrical design or something else.

But we're basically using relays from the Opta to drive relays on this board, which are also rated for 10 amps. So you're basically dual ch-channeling the relays for whatever reason. We do have a voltage regulator, right? And I'm assuming, yes, this is going to the ESP32 board on the breadboard. They've mentioned that they will remove this.

Again, these are embedded electronics that you are unlikely to see in the industrial space without a specific enclosure. I would recommend if you have the time and you have the access to that hardware to 3D print, and here we, we can't see it very well here, but you can 3D print the enclosures that you can mount on a d-din rail.

We have an E-stop. Again, not very clear where the E-stop is going because an E-stop requires some kind of a safety relay, but it is wired somewhere. And we have this piece of embedded hardware. Again, not sure if this is a regulator. Maybe this is stepping the voltage down further. Very unclear at this time.

And then we have some field connectors. If you've worked with these, these are basically terminal blocks that you can plug in another wire from underneath and be able to wire this in. Let's look at the second image, which doesn't reveal a whole lot more. So this is the same panel. One thing I will notice is that the wire trays are very neatly organized, so I think that is a huge plus.

We do have proper termination on the wires. So again, we're looking at the crimped stack-ons at the end of every wire, and that has been properly implemented. Like I said, there's a few improvements that could be made but overall, I think this is good. I believe that you can also probably save a ton of real estate space by, again, if you just move these terminals over and rearrange a lot of this, you can probably half the size of your panel.

And a lot of your electronics don't necessarily generate that much heat. All you have is a PLC, a power supply, and a few of these smaller embedded solutions. But you can basically cut down the size of your entire panel in half. And typically, I would say again, for demo purposes, it doesn't really matter, but in the industrial space, real estate usually comes in at a premium, and it's unlikely-- Obviously, you may expand the panel, but you can simply put everything here and leave the extra space at the bottom.

Those would be my only comments. I think this is an excellent build for a capstone project. I would not have expected to see anything of this nature in my university, at least at the time of studying. And of course, the Opta wasn't released back then. But I think this is an excellent build. This is really good practice.

Land the ground and research dual channel safety

I think that you can certainly use LLMs also to get some feedback. And again, take the extra time maybe to land the ground because it is something that you generally need in your circuits. It is something that is required for safety. I would also research the E-stop. You want to have dual channel safety.

Maybe the hardware is expensive, but at least to understand what it takes to properly shut down the system and where this actually needs to land. Because again, if you only have a breaker with a power supply, this E-stop isn't necessarily going to cut off the power to your entire panel the way it is currently wired in.

Do PLC programmers need electrical wiring knowledge?

Next, we have a career question, and of course, having been over a decade in the industry, I am always curious to hear what some of the questions are and obviously looking to help some of those entering our industry So this question comes from the username pan03237, and they say, "If you work with PLC programming, do you also need knowledge of electrical hardware and wiring?

Hello, I'm a young engineer working with PLCs and DCS systems in South Korea. In Korea, if you work in PLCs or DCS, you are generally expected to have a basic understanding of electrical hardware and electrical engineering, as well as some practical knowledge of wiring. Is it the same in other countries?

Are PLC/DCS engineers generally expected to have knowledge of hardware and electrical wiring as well?" So let's take a look at some of the answers, right? So people say, "Absolutely." Fu2made joke, "Sorry, I had a typo in the title. I spent a long time trying to figure out what I meant before I noticed it. You must be an expert in all related instrumentation electrical systems if you want to be a competent control systems engineer.

Also pneumatics, a bit of mechanics, industrial networking, depends of the industry. You must know about hydraulics, robotics, motion. So yes, at least instrumentation and how to wire a panel from scratch is the very basic." So again, what is my general perspective? So I studied electrical engineering, and I had a very solid foundation of, I would say, bulk

a very solid foundation of book knowledge and skills going into the workforce. So for me, on the electrical side, it was not an issue to learn about the industrial side of things and how things are done in the industrial space. Now, I can tell you that is not the, I would say, the general path of everybody going into the industry.

I have worked with electricians that worked their way up to control systems engineers and, and management for that matter. I have worked with people from, coming in from other industries that had no previous electrical background going into PLCs, DCS, SCADA systems. So it really depends, first and foremost, I would say, what is your focus?

Are you going to troubleshoot systems in the field? Are you going to commission built systems? Are you going to program PLCs and HMI? Are you going to program SCADA and MES and solve some of those higher level problems that are Present in manufacturing. Now of course, the focus here is if you work with PLCs or DCS, the answer would be absolutely, you need to understand electrical systems.

A lot of times if you're going to select a specific controller, right, so I'm pointing at the Siemens S7-1200G2 series, or if you're going to select a productivity line from AutomationDirect, you will be specifying the inputs and outputs of electrical nature that will be driving or receiving signals from a variety of different loads.

Now, it- there is a comment to be made if you're a pure design, quote-unquote, engineer, it's possible that you create the drawings and then you pass them on to either operations or field engineering that will then go and commission the actual system with you not needing to touch anything that has to do with the actual physical wiring.

I would say that those positions are much rarer in the industry. A lot of times it is preferred that the person that has designed the system will go in the field and commission said system.

Engineers vs technicians at large manufacturing plants

Now, when it comes to actual plant work, right, so I have worked for Procter & Gamble, I have worked for Kraft Heinz, fairly large companies.

Typically, you do have some separation of tasks between engineers and technicians. So technicians will focus a lot more on routine maintenance tasks. They will do the majority of, I would say, minor troubleshooting tasks, and the engineers will only be called when there is an actual breakdown that nobody else can figure out, and you become the last line of defense, so to speak, in those technical situations.

Now of course, in that instance, it is possible for you to either adopt the stance of, "I need a technician who's going to, for example, measure the voltages, who's going to troubleshoot some of the wiring", or in some cases, if it's not a union plant, you can do it yourself Now, of course, with that in mind, the general expectation is that you understand the electrical systems, you understand the voltages that they carry, the currents that they carry.

Is it expected for you to have all the calculation in mind? I would say no. Generally speaking, you would go inside of manuals. You will get on the phone, for example, with the OEM. A lot of the plants that I have worked with, again, in North America specifically, have a contract with Rockwell Automation where you can call upon TechConnect, which is a paid service that will guide you through some of the challenging problems you might be facing specifically with their hardware.

So the expectation is gonna be different industry to industry, plant by plant. But I would say in the majority of cases, as the electrical control systems engineer, you are expected to have the knowledge of electrical systems because not only you're specifying some of that hardware that will be the interface, but also you will help in troubleshooting or at the very least commissioning some of those systems

What a control systems engineer at a mine does day to day

All right, we've got one last question, which is again industry specific, and it comes from an industry that I'm not overly familiar with, but I've had some projects in the past, and of course I talk to a lot of different colleagues in the mining industry And so this comes from the username YoLardin, and they say, "What does a control system engineer at a mine do day to day?

Hi, everyone. Just curious what the day-to-day work looks like for a control systems engineer at a mine. Where I work at an oil refinery, we maintain both field instrumentation and control systems. Most issues tend to be with instruments, valves, wiring, et cetera. We go into the PLC/DCS for troubleshooting and maintenance when needed, but actual control system failures are pretty rare, and we don't spend much time changing logic.

So I'm curious how it works when process control is a separate dedicated role when everything is running normally. What takes up most of your time? Also, are you usually the only control person on site as part of a larger team? Where does your responsibility and the instrumentation team begin? Would be good to hear what a typical day or week looks like."

I, again, based on me reading this, I can immediately tell that the environment is going to be very similar between an oil refinery and a mining site. The major thing that changes how many engineers and how the tasks are broken down as are going to be the size of the operation and or company. So I talked to, like I said, a lot of different engineers in oil and gas, in mining of different materials.

I've talked to engineers that go in deep into mines, and I've talked to engineers that work in basically open mines, and they tell me pretty much the same thing as described here. So there's a mix of troubleshooting field devices and field control systems as well as execution of specific projects.

And so I would imagine that in a broader sense, based on the question that is asked here, the time allocation is very similar unless you go to a much larger team in which you will have, for example, four or five engineers, two of which, which may be a lot more focused on the field side and two to three of which might be focused on longer term improvement type of projects.

When everything runs normally: projects, shifts, and team structure

When everything is running normally, what takes up most of your time? Again, I've been in different environments and it is always almost the same case. You're not twiddling your thumbs as a control systems engineer. So if everything is working well on the plant floor, usually you have long-term projects you can work on and you need to deliver on time with other teams.

So you're either sitting in meetings, you're talking with IT, you're talking with vendors, you're reviewing designs, you're working with contractors that will be there for commissioning, so on and so forth. Are you usually the only controls person on site or part of a larger team? Where does your responsibility end and the instrumentation team's begin?

Again, companies handle this very differently in my experience. So like I said, at smaller sites, it is possible that you don't even have a dedicated control systems engineer on staff. You would rather have a technician that will go and make sure that everything is working as expected. They work on a shift basis, so it's predictable when they are there and when they are not.

If there is a control systems engineer, usually they will not be on both shifts, right? Because they cannot cover a twenty-four-seven operation. So they will typically be on days. They will be helping out with some of the problems on the day shift, but they will also be reviewing some of the data from the previous breakdowns, maybe looking at RCA information, so on and so forth.

And if it's a larger team, again, you sometimes have a clear divide of responsibilities where some of the engineers are focused on the day-to-day. Some of the other engineers are focused on the bigger picture and site improvement projects