Automate
PLC programming services — new systems, migrations and rescues
We write PLC code that the next engineer can read. Structured, commented, consistently named, with a clear state model and documented I/O — because the cost of a control system is not what it takes to write it, it is what it takes to change it three years later at two in the morning.
The problem
Most plants are one retirement away from a control system nobody understands
Undocumented ladder logic with tags called M0.3, no version control, no as-built drawings, and one person who knows how it works. It runs perfectly right up until it does not, and then a stoppage that should take an hour takes three days.
- 01
Nobody can explain what a section of the program does
- 02
There is no source code, or several versions and no way to tell which is running
- 03
A controller is obsolete and spares are only available on the used market
- 04
Changing anything is avoided because the consequences are unpredictable
- 05
The machine is a black box that reports nothing to anyone
What we build
Concrete deliverables
Nouns, not adjectives. This is what actually gets handed over.
- 01
New PLC development
Full control programs written to a documented standard — structured text, ladder or function block as appropriate — with simulation before commissioning.
- 02
PLC migration and modernisation
Moving obsolete controllers to supported platforms with functional equivalence proven, phased cut-over and a defined rollback.
- 03
PLC integration
Connecting controllers to HMIs, SCADA, drives, robots, vision systems, weighing systems, printers and upstream software.
- 04
Troubleshooting and rescue
Reverse-engineering, documenting and stabilising systems that were inherited without documentation, often mid-crisis.
- 05
Code documentation and standardisation
Turning an undocumented program into a maintainable one: naming, comments, structure, drawings and a functional description.
- 06
Remote monitoring of PLC data
The layer most PLC vendors do not deliver — getting the controller's data out to dashboards, alerts and reports securely.
How it works
The technical path, step by step
Where the engineering decisions actually get made.
- 01
Establish the truth
Read the installed program, verify the I/O against the field, and write down what the system actually does — which is often not what the drawings say.
- 02
Functional specification
Sequences, interlocks, alarms, modes, and failure behaviour, written down and signed off before code changes.
- 03
Develop and simulate
Code written to a naming and structure standard, tested in simulation or against a test rig, and reviewed before it reaches the plant.
- 04
Commission
Loop checks, dry run, staged cut-over inside your window, with the previous program retained and restorable.
- 05
Document and hand over
Commented source, as-built I/O schedule, functional description, and a walkthrough with your maintenance team.
Protocols & technologies
Specifics, because vague answers cost you money later
Chosen per site according to what is installed, not according to what we would prefer to work with.
| Technology | Where it is used | Engineering note |
|---|---|---|
| Siemens S7-1200 / 1500 | TIA Portal | Current mainstream platform for new work in India. |
| Siemens S7-300 / 400 | STEP 7 / TIA migration | Very large installed base; common migration source. |
| Allen-Bradley CompactLogix / ControlLogix | Studio 5000 | Common in automotive-tier and multinational plants. |
| Allen-Bradley MicroLogix / SLC | Migration source | Obsolete; migration to CompactLogix is a frequent request. |
| Mitsubishi FX / Q / iQ-R | GX Works | Widespread in machine-builder equipment. |
| Delta / Fatek / Wecon | Cost-sensitive machine control | Very common in Indian SME machine builds. |
| Schneider M221 / M241 / M580 | EcoStruxure / Unity | Common in process and utility applications. |
| Omron CP / CJ / NX | Sysmac / CX-Programmer | Frequent in packaging and material handling. |
| Modbus / OPC UA / Ethernet-IP / Profinet | Controller-to-system communication | How the PLC talks to HMI, SCADA, drives and the data layer. |
Brownfield
Migration without a shutdown you cannot afford
An obsolete PLC does not have to mean a plant-wide stoppage. We build the new program, prove functional equivalence in simulation, pre-wire and pre-test the new panel, and cut over inside a planned window — with the original controller kept intact and restorable until the new one has run a full production cycle.
Works with
- Obsolete Siemens S5 and S7-300/400 systems
- Allen-Bradley SLC 500 and MicroLogix
- Mitsubishi FX legacy series
- Undocumented programs with no available source
- Machines whose original builder is no longer in business
Use cases
What people actually ask us for
Each one is a situation followed by the outcome it produces — not a feature list.
Obsolete controller replacement
NowSpares are unavailable and a failure means an extended stoppage.
AfterMigrated to a supported platform, functionally verified, fully documented.
Inherited undocumented machine
NowA second-hand machine arrived with no program listing and no drawings.
AfterProgram read, documented, I/O verified, functional description written.
PLC to dashboard
NowThe controller has the data; nobody upstream can see it.
AfterRead-only data path from PLC to dashboards and alerts, with no change to control logic.
PLC–SCADA integration
NowA new SCADA system needs tags the PLC does not currently expose.
AfterTag structure designed, exposed via OPC UA, and mapped consistently across controllers.
Recipe and parameter management
NowChangeovers depend on an operator entering the right numbers.
AfterRecipe handling in the controller, driven from HMI or from a higher-level system, with change logging.
Intermittent fault diagnosis
NowA fault that appears once a week and never when anyone is watching.
AfterHigh-resolution logging around the event so the cause becomes visible rather than theorised.
Implementation
How a project runs
Eight stages, each producing something you own. Full detail on the process page.
- 01
Discover
1–2 conversations
- 02
Audit
1–3 days on site
- 03
Design
1–2 weeks
- 04
Engineer
2–8 weeks per phase
- 05
Integrate
1–2 weeks
- 06
Deploy
Your shutdown window
- 07
Monitor
First 4–6 weeks
- 08
Optimise
Ongoing, if you want it
PLC to dashboard, without touching the control program
The design we would propose for the most common request we get: 'the PLC knows, but nobody upstream can see it.' Published in full so it can be judged technically.
Read the write-upQuestions
PLC Programming — common questions
Which PLC brands do you program?
Siemens (S7-1200/1500, S7-300/400, TIA Portal and STEP 7), Allen-Bradley (CompactLogix, ControlLogix, MicroLogix, Studio 5000 and RSLogix), Mitsubishi (FX, Q, iQ-R), Delta, Schneider, Omron, Fatek and Wecon. Where a platform is outside our direct experience we say so rather than learning it at your expense.
Can you work on a machine when we have no source code?
Usually yes. Most controllers allow the running program to be uploaded, which gives us the logic even without comments. From there we verify I/O in the field and reconstruct a functional description. It takes longer than working from documented source, and we scope it as investigation work with a checkpoint before committing to changes.
How do you handle a migration safely?
The new program is built and proven in simulation first. The new hardware is pre-wired and pre-tested off-line where possible. Cut-over happens in an agreed window with the original controller kept intact, so reverting is a physical swap rather than a rebuild. We do not cut over on a Friday evening.
Do you follow a coding standard?
Yes — consistent naming, structured program organisation, meaningful comments in English, clear separation between sequence, alarms and I/O mapping, and a documented state model. If you already have a corporate standard, we work to yours instead.
Can you get PLC data into a dashboard without touching the control logic?
In most cases, yes. Reading existing registers or tags over Modbus TCP, OPC UA or Ethernet/IP is non-intrusive. Where a value is only held in an internal variable and not exposed, a small, carefully scoped addition may be needed — we identify that during the survey and tell you before quoting, not after.
Do you provide support after commissioning?
Yes, under a defined arrangement — response times, scope and remote access conditions agreed in writing. We also hand over full documentation and source code specifically so you are not dependent on us. Both things are true at once, and deliberately so.
Send us the controller details
Make, model, what it runs, and whether you have the source. We will tell you what is realistic and what it involves.