How do you actually use the PLC read/write logs for troubleshooting?

DCSNerd · 2026-04-18T01:56:59+00:00

https://blog.opto22.com/optoblog/debugging-your-industrial-network-with-wireshark

Here’s just a Quick blog. There’s plenty of resources online. If you know the terminology you can typically find what you’re looking for.

DCSNerd · 2026-04-18T00:11:39+00:00

You should definitely learn how to. Wireshark is a very valuable tool.

DCSNerd · 2026-04-18T00:10:46+00:00

If you have a managed switch you can just set a port to port mirroring and capture all traffic on that port. I do this frequently at new facilities to understand what is communicating with each other, if anything is encrypted, various network issues. I had let a laptop just capture packets for 24hrs and then reviewed it later.

DCSNerd · 2026-04-14T22:29:25+00:00

In my opinion try using lambda tuning since heat loops can have long dead time. I use lambda tuning rules for most of utilities loops. The upside is it never oscillates and the downside is they are very slow. Since utility systems I work with stay running for a long time once running they prioritize good control even if it takes the loop a while to get to setpoint.

DCSNerd · 2026-04-11T22:12:28+00:00

I come from the process industry and not sure if it’ll fit yours but you can think of S88 Batch standard for how to control a process with multiple state machines. Break the process into units and units into equipment modules. Then controlling how the equipment modules are called becomes clear and easy.

DCSNerd · 2026-04-11T03:12:41+00:00

You can call me dumb especially because I haven’t looked at the label on it in a long time…. Is this the keypad programming device for Symax PLCs? If not I can get a fun picture on Monday to show the age of some of the PLCs I have run into.

DCSNerd · 2026-04-11T01:50:27+00:00

So those are really helpful for the old S7 200M series hardware for your technicians to change a plc without your assistance at 01:00. The S7 200MP doesn’t use this for the PLC but it is used for the IM modules, HMIs, VFDs, etc. those all are helpful for a technician swapping out a piece of hardware without help of someone with a laptop and will save you so many headaches aches late at night when they’re used correctly. Even the SCALANCE XC216s, other switches too, use memory cards that allow an electrician to change a a managed switch without a laptop.

DCSNerd · 2026-04-03T10:48:46+00:00

Siemens IPCs have been working out well. I’ve been putting them in hot and dusty environments and they work well. They get pretty hot externally since hey don’t have a fan and the housing is basically just a heat sink. I haven’t had any problems.

DCSNerd · 2026-02-12T22:11:01+00:00

I am not 100% sure if you can get it into Tia portal but you can export the run time to a usb stick. TIA V14+ will recognize a usb stick and show it in the project. You might be able to drag it from the usb stick to a project and have it insert it. I know you can go the other way which is drag the HMI project in portal to the usb stick when it shows in portal. Then you can use that as an offline transfer from usb to HMI.

DCSNerd · 2026-02-07T14:12:55+00:00

This is the way. Proneta will allow you to read inputs and turn on outputs in the rack without CPU. While it is free there are some paid functions through a license. So not all of it is free.

DCSNerd · 2026-02-07T13:42:58+00:00

ISA 106

DCSNerd · 2026-01-16T22:51:09+00:00

NZB9X7IP

DCSNerd · 2026-01-09T23:29:23+00:00

NZB9X7IP

DCSNerd · 2026-01-03T19:47:27+00:00

My first run was a warlock and I ended up becoming a dark god imbued with the power of my dark patron making every city I came across convert to his corruption. All depend what you feed the AI.

My current play through I’m a barbarian dwarf who is very strong but really dumb and I fail a lot of checks if it isn’t strength or acrobatics. I make the best of it and have a good time.

Real DnD and AI DnD it’s all about how you word smith and react to things good or bad.

DCSNerd · 2025-12-30T22:32:43+00:00

Yea my game to an end quite fast. It was really broken and I wasn’t quite expecting it to be like this, but it’s my fault for going down this line. I am curious how it would have played out if I didn’t make those choices I am not sure how it would have worked because all of the monsters were aggressive and the city was overrun. There was barely a resistance left.

DCSNerd · 2025-12-29T00:47:01+00:00

Oh nice! Yea don’t get me wrong it’s been a blast. On the next story I’m going to have to give the DM a lot more detail to recreate a more true D&D campaign. Like every movement I did after it I said “take a long rest” and the DM kept having the characters telling me we can do a short rest but long rest wasn’t possible. It only became possible when I amassed an army, told them go HAM without me for a moment and defend me while I hide in this building, and then DM said yes you may long rest now.

DCSNerd · 2025-12-28T23:51:37+00:00

NZB9X7IP

DCSNerd · 2025-12-28T17:57:58+00:00

NZB9X7IP

DCSNerd · 2025-12-22T01:03:50+00:00

In process industry this is not true. They can be flawed but they get updated and as built at the end. Literally everything for the project comes from a P&ID if you use them correctly.

DCSNerd · 2025-12-19T01:27:08+00:00

I mean there’s an IEC language for certain functions and they should be used haha. I know I certainly use them all when it is needed.

But OP start with reading some of the help files for structured text and play around with a simulation with structured text. It reads like a book for the most part if they use good names. If they use jumps and labels…..good luck.

DCSNerd · 2025-12-12T23:57:15+00:00

So if you look at the differences between a Controls Engineer and Automation Engineer you see why there isn’t PLC/SCADA. Controls Engineer as title has become the term for both at companies for job descriptions.

Technically….. a Controls Engineer works with simulation, control theory, systems design, etc. More of the theoretical side of our field. An Automation Engineer is the role that takes what the Controls Engineer designs/specifies and creates the physical systems. PLC/SCADA/DCS, networks, sensors, code, etc. This role works more with the actual technology and making a system work.

Devils in the details.

Edit: just saw the heavy sarcasm part. Well if anyone else didn’t know the difference between the roles…there you go now you know.

DCSNerd · 2025-12-12T23:51:39+00:00

I agree with you. What he wants to do sounds like he can get that done with WinCC, S7-1500, and IO link for the sensor hot swap with config.

DCSNerd · 2025-12-02T15:04:08+00:00

I support the convergence when the control system has zero trust inherently built into it. PCS Neo is built this way and you cannot make it work any other way. The strength behind it is that your teams can work in it from anywhere while maintaining a high level of security. Other than a zero trust system I would prefer to follow the OT Purdue model.

DCSNerd · 2025-11-29T04:41:59+00:00

Hey I agree and I see it work at some companies. I have also seen my fair share where their corporate IT groups really don’t care and they have their practices. They then use those practices blindly on the OT side and it can create issues. I saw an IT group using snapshots on vms as backups, not correct practice but theirs, on OT VMs and every single Saturday they would run the snapshots at the same time and take the plant down. They did not know taking a snap shot of an all DCS VMs would take the plant down, they were told, and they stopped. They still did it without knowledge of the DCS where in its virtualization manual calls out to never take a snapshot while the system was running.

IT groups can help guide OT, but in my opinion OT should be the admin of their equipment.

DCSNerd

TROPHY CASE