1. Record the installed platform

Identify the IPC or controller, TwinCAT build, connected-device firmware and actual running PLC configuration. The project on an engineering laptop may not match the version running on the machine.

  • Confirm TwinCAT 3 build, target platform and runtime configuration.
  • Document EtherCAT topology, I/O terminals, drives and communication interfaces.
  • Identify HMI, safety-controller and third-party integrations.

2. Back up the project and plan recovery

Keep an approved copy of the source project and relevant configuration before making changes. Agree on a tested recovery approach. A backup by itself does not guarantee a successful rollback.

  • Archive source projects, library dependencies and version details.
  • Record current boot settings and changed configuration parameters.
  • Agree stop criteria, access and who may authorize recovery.

3. Review EtherCAT and drive interfaces

Changes to process data, I/O mapping or drive parameters can affect more than the individual PLC program block. Plan verification of signals, timeout behaviour and any motion functions.

  • Compare the running configuration with the documented machine hardware.
  • Check affected sensors, actuators, axes and external interfaces.
  • Coordinate any safety-related changes separately with the responsible site team.

4. Define tests before downloading changes

A successful compile does not prove that the complete machine behaves correctly. Agree on tests for normal operation, relevant faults, HMI signals and communication. Use simulation or an offline test environment where possible.

  • Document expected signals and sequence transitions.
  • Verify start, stop, alarms and important interfaces.
  • Plan an approved maintenance window and suitable personnel.

5. Complete the technical handover

Record the deployed version, changes and test results. Provide the customer with a maintainable source project and updated relevant documentation.

  • Archive change log, test evidence and approval.
  • Update required I/O, PLC/HMI and operational documentation.
  • Agree a follow-up route for post-commissioning issues.

Do not email passwords, access keys or confidential source projects. Work on live equipment, particularly safety-related functions, requires the customer's approved risk assessment and change procedure.