Retrofit · diagnostics · program rescue
A line stopped, a program was lost, interlocks trip randomly, an old machine needs upgrading — these are program and logic problems. We work evidence first, conclusions second. We do not guess.
When to call us
Program lost or overwritten after a shutdown; wrong program or parameters after replacing a PLC or module; interlocks tripping often with no root cause found; an old controller (S7-200/300 or a third-party brand) to be upgraded to S7-1200/1500; a program written by someone else that needs readability and defect review; no version control, needing a baseline.
Typical work
- Program rescue and recovery: rebuild a usable version from backups, uploads or remnants — consistency checked before handover
- Root-cause location: section-by-section review against scan cycle and timing, with ranked hypotheses — not trial-and-error edits
- Interlock and safety-loop review: list every interlock condition and verify each one is reachable and cannot be bypassed
- Legacy upgrade: restructure POUs, normalise naming, complete documentation and verification records
- Archiving and version baseline: establish a traceable version so this does not happen again
How we diagnose (three steps)
Remote vs on-site
Boundaries (so we do not take the wrong job)
- No hardware repair or component replacement: power modules, I/O boards and HMIs are hardware repairs — use a repair shop
- No electrical installation or switchgear supply (control programs and verification only)
- Functional safety sign-off in high-hazard plants must be done by a qualified body
What helps us most
A description that reproduces the problem: when it happens, what was done beforehand, what the symptom is; the most recent program backup (if any); PLC model and firmware version; whether remote access is possible or an uploaded program file can be shared. The faster these arrive, the faster we locate it.