Can you practise PLC programming without hardware?
Yes, and a large part of the skill transfers. Simulation teaches logic, sequencing, HMI design and fault-finding against a virtual process. What it cannot teach is wiring, earthing, noise and the physical failures that make up much of real commissioning work — so use simulation to build logic, and treat hardware time as a separate requirement.
The 12, ranked by what they teach
| # | Method | Cost | Teaches |
|---|---|---|---|
| 1 | Factory I/O + a PLC or soft PLC | Paid (trial available) | Full sequencing against a 3D process |
| 2 | CODESYS + simulated I/O | Free | IEC 61131-3 languages, structured text |
| 3 | TIA Portal trial + PLCSIM | Free trial | Siemens workflow, the market leader |
| 4 | A second-hand S7-1200 or CompactLogix | Paid | Real download, real I/O, real faults |
| 5 | Build a small panel | Paid | Wiring, terminals, safety circuit |
| 6 | OpenPLC on a Raspberry Pi | Very low | Runtime concepts on cheap hardware |
| 7 | Re-create a real machine from a video | Free | Requirements-to-logic translation |
| 8 | Ignition trial (SCADA) | Free in trial | Tags, historians, alarming |
| 9 | Modbus between two devices | Low | Protocols made concrete |
| 10 | Write the documentation | Free | The skill employers say is missing |
| 11 | Vendor manuals and app examples | Free | How professionals structure code |
| 12 | Teach someone else | Free | Exposes what you only half know |
What should you actually build?
Projects with states and edge cases, not single rungs. Good candidates: a three-station conveyor with jam detection; a batch mixer with recipe selection; a traffic junction with pedestrian demand; a car-park counter with full/empty logic. Each forces sequencing, timers, interlocks and an HMI.
How do you turn practice into something an employer values?
- Record a short screen capture of the sequence running, including a fault you inject
- Write a one-page functional description — what it does and why
- Keep the code readable: comments, meaningful tag names, structured routines
- Be able to explain a bug you fixed — this is the part interviewers probe
Compare the tools in 8 PLC simulators compared, and see what interviewers ask.