Are You Asking the Right Questions: Commissioning
Commissioning is a multi-staged process that is designed to ensure that a data center operates as designed. Despite its critical nature, it is often viewed as an afterthought by many prospective customers and a necessary evil by some data center providers. However, if we compare commissioning to test flying a new aircraft, it is easy to see that obtaining space in a fully commissioned facility is a customer’s best protection against catastrophic and costly site outages. Due to the importance of the commissioning process to the ultimate operation of the data center you need to understand just how a potential provider will perform this testing on your new facility.
Commissioning consists of five levels, with levels four and five being the most important for our discussion here. Level 4 commissioning consists of powering up all of the data center’s equipment to ensure that each component operates as required. Level 5 commissioning is the essential component of the commissioning process since all of the site’s systems are tested at both peak loads and in a variety of failure scenarios to ensure that all of the data center’s systems work as designed. As we shall see, the most critical aspect of Level 5 commissioning is the ensuring that the site is able to surmount critical failures such as a power outage to maintain operation.
The functional design of a data center is intricately intertwined with its ability to complete the full five levels of the commissioning process. Many data center alternatives use a single MEP backplane. Analogous to a power strip each new data center is “plugged into” the backplane as it is added. Although commonly used, architectural designs with “future growth phases” based on this concept can only complete the first four levels of the commissioning process. This is due to the fact that, just as when the power is turned off to the power strip, the failure mode scenarios required in Level 5 cannot be performed since turning off the power brings down all of the attached data centers during expansion. The other alternative in backplane design is to use discrete backplanes for each data center. In this structure each data center operates independently from its companions. As a result, new data centers can be fully Level 5 commissioned since simulating a power failure for testing does not negatively impact any existing data hall. Thus, the backplane structure of a data center solution determines its ability to undergo a complete commissioning process when expansion is necessary.
Container-based solutions use a “backplane” structure that is best described as a “daisy chain”. Based on our descriptions above this design would fall within the single backplane category. Thus, while the very first container could complete all five levels of the commissioning process each subsequent module added could not.
Monolithic modular structures that use pre-fabricated or built out data halls can use either the single or discrete backplane methods so it is important to ask your prospective provider if your new data center will be Level 5 commissioned. Some providers have elected to “fudge” the commissioned status of their facilities by advertising them as simply “commissioned”. Treat this as the red flag that it is.
Since they are designed to be the equivalent of “shrink wrapped” products that include all customer-required attributes in a single package, standalone data centers are constructed with a dedicated backplane per module. This conscious design component enables each new module added to the data center to be fully Level 5 commissioned, and is able to operate efficiently under peak loads and in the event of what otherwise would be a service-interrupting event.
Failure to complete a full Level 5 commissioning process is analogous to purchasing a product that is only 90% complete. Operating your new facility on faith is akin to flying in that untested airplane. Sure, it may fly but wouldn’t you feel better knowing for sure, before you boarded?