Document the system you actually have, not the system the drawings say you have.
A migration project becomes harder when field hardware, software versions, network dependencies and drawings have drifted apart. This survey creates a reusable baseline before design begins.
Minimum evidence set
Hardware
Controller, chassis, power supply, I/O, communication modules, specialty cards and installed revisions.
Software
Engineering package, version, license method, project file, libraries and required operating system.
Networks
Protocols, node addresses, IP settings, gateways, remote I/O and third-party dependencies.
Process interfaces
I/O count, signal type, scaling, interlocks, drives, HMI/SCADA tags and safety boundaries.
Backups
Verified program backup, HMI project, drive parameters, network configuration and restore notes.
Drawings
Cabinet layout, wiring, loop drawings, network topology and change-marked field corrections.
Build a survey record
Field-survey workflow
| Stage | Action | Evidence |
|---|---|---|
| Desk review | Collect drawings, asset lists and old project files. | Document register. |
| Cabinet survey | Photograph labels and record physical slot order. | Timestamped field record. |
| Software review | Open backups and identify required tools. | Verified project files. |
| Network survey | Map interfaces and dependencies. | Current topology. |
| I/O verification | Compare configured and field-connected signals. | Corrected I/O list. |
| Migration baseline | Freeze the accepted pre-design dataset. | Revision-controlled baseline. |
Reusable worksheet
Download legacy-system survey CSVMaintainer
Maintained by PLCProTech Ltd. as an open industrial automation engineering reference.