Commissioning is demonstrating, in testing, that the delivered infrastructure behaves as designed. In a data center, the right time to find an error is before the IT load is switched on.
The levels
The most common practice organizes tests in five levels. Level 1: factory verification of equipment. Level 2: inspection of the installation on site. Level 3: start-up and operational verification. Level 4: performance tests of each system. Level 5: integrated testing, where systems are exercised together, including simulated failures.
Integrated testing reveals the most
It is at level 5 that you see whether the transfer to generator works with cooling reacting at the same time, or whether a communication fault brings down a control. Interface problems rarely show up in isolated tests.
Plan it together with the design
When the test plan is born with the design, acceptance criteria are already defined and the design provides test points and load banks. Leaving commissioning to the end usually means a tight schedule and cut tests.
