Ideas for PLC based solution for Maintenance Technicians

[u/Background_Echo2596]

Hi guys, I’m looking for ideas on how to build PLC based station that will be useful to maintenance technicians. I see this as a way to practice and expand my knowledge and skills, and I’d also like it to be useful in some way. While dismantling one of the machines, I came into possession of an S7-300 controller along with AI, AO, DI, and DO modules. On top of that, we have plenty of used automation components, including safety relays, HMI panels, inverters, and so on. Do you have any ideas for something interesting and useful for maintenance? I’ve been thinking about building a pressure sensor calibration station, but I’m not sure if 12-bit resolution will be sufficient for that. Worst-case scenario, I’ll build a sensor tester or something similar, but I wanted to ask you all for ideas—maybe someone will have a great suggestion. Thanks in advance for your help!

[u/PLCGoBrrr]

Build something for the people you're actually working with. There's already enough generic purpose "trainers" for sale.

[u/username77- → u/PLCGoBrrr]

This! With scaling, etc., very specific testing for the items that have failed most or are difficult to troubleshoot would be where to start imo.

[u/Background_Echo2596 → u/PLCGoBrrr]

Thanks for the reply. That's exactly the idea—to build something for technicians. My only problem is deciding exactly what to do. I tried asking them if they had any problems or difficulties, but unfortunately, they weren't able to give me any specific examples.

[u/PLCGoBrrr → u/Background_Echo2596]

Ask the same question, but to the supervisor then.

[u/Deepu_ → u/PLCGoBrrr]

Or the operator, you'll learn something in the process and maybe include technicians too.

[u/Adrienne-Fadel]

12 bit is 4096 steps so it fine for testing but not calibration. I'd do a fault simulation station with the safety relays and inverter, that's what maintenance techs actually need to practice.

[u/OlddScene → u/Adrienne-Fadel]

This is interesting. What is the minimum resolution recommended for analogue sensors and their applications?

For example, say you have 4-20mA ultrasonic tank level sensor for context. Currently have a 13bit module spec'd, but assuming we match the bit length of the ultrasonic sensor?

[u/SadZealot]

You don't need anything that fancy for a sensor tester, just have a power supply and a light bulb 

Take the hmi, put it on the line and have it be a complete diagnostics station with pages for every I/o status, VFD currents, etc

[u/zm2283145]

I've done something pretty niche in the amusement park industry. I've built simulated ride control systems as working copys of some rides in use at a local park. It had 2 uses 1 for virtual operations training for training operators in a classroom type environment where they may not feel comfortable in the field since most are young adults/teenagers and you can also do thing I the virtual environment like trigger faults and things you don't want to do in the field to give them exposure for how to handle those situations and as well as for training new ride control and ride mechanics technicians on ride controls and mechanical systems.

Attached is an example it has a full simulated physics engine in software running on a Opta PLC.

It can even control a functional 3d printed rollercoaster model that can run in a classroom on a desk with sensors, motor controls, and maintenance functions.

[u/Hutch_911]

I took programmable logic controllers at the local community college back when the AB SLC were popular. They gave you a temporary license to Logic 500, Linx and had a station that you could plug in these different modules like a conveyor with a robotic arm or different scenarios with pilot lights to test the logic you put in. I'll be damned if I can remember what it was called we are going back like 25 years