PLC and SCADA commissioning is the process of testing, calibrating, and verifying an industrial control system before it goes into full production, confirming every input, output, and safety interlock behaves the way the design intends. For facility managers in Alberta and BC, it is the step between installed and operational.
What Commissioning Actually Covers
Commissioning is not a single test. It is a sequence of checks that confirm the control system matches the design and performs correctly under real conditions.
- I/O point-to-point verification, confirming every signal reaches the correct terminal
- Loop checks, confirming sensors, controllers, and final control elements work together
- HMI and SCADA screen verification against the P&IDs
- Interlock and safety system testing, including emergency stops and permissives
- Performance testing under actual process load
Why Skipping Steps Costs More Later
A wiring error that gets missed during I/O verification does not disappear. It surfaces during production, usually at the worst possible time, as an unplanned shutdown, a false trip, or a reading that does not match what is actually happening in the process. Full commissioning costs time upfront. Skipping it costs more in downtime later.
Typical Commissioning Timeline
Pre-commissioning covers documentation review, panel inspection, and initial power-up in a controlled state. Cold commissioning tests logic and I/O with the process not yet running. Hot commissioning brings the system online under live process conditions, with the crew watching for anything that behaves differently than it did in testing. A mid-size facility retrofit typically runs two to six weeks from pre-commissioning through full hot commissioning, depending on scope and how much of the control system is new versus modified.
Who Should Be on Site During Commissioning
An instrumentation technician handles field devices and loop checks. A controls engineer or programmer verifies logic and troubleshoots anything that does not behave as designed. A process operator who knows the equipment should be present for hot commissioning, since they are often the first to notice when something is technically correct but operationally off.
Common Commissioning Delays and How to Avoid Them
- Incomplete or outdated as-built documentation, which slows down every verification step
- Vendor equipment arriving without factory acceptance testing completed
- Communication protocol mismatches between the PLC layer and the SCADA layer
- Safety interlocks tested last instead of early, delaying sign-off at the end of the schedule
Frequently Asked Questions
What is the difference between a PLC and a SCADA system?
A PLC, or Programmable Logic Controller, is the hardware that executes control logic in real time at the equipment level. SCADA, or Supervisory Control and Data Acquisition, is the software layer that lets operators monitor and control multiple PLCs from a central interface.
How long does industrial commissioning take?
It depends on scope, but a mid-size facility retrofit typically runs two to six weeks from pre-commissioning to full hot commissioning.
Do I need full commissioning for a small PLC upgrade?
Yes. Even a single-PLC swap needs I/O verification and loop checks to confirm nothing shifted during the changeover.
Pro Call Electric commissions PLC and SCADA systems for industrial facilities across Alberta and BC. See our industrial services or contact us to talk through your next commissioning project.