Commission, Test UPS To Ensure Proper Operation
May 1, 2014
A data center UPS plays a critical role in keeping the data center operating the way it's supposed to, and it's up to FMs to make sure it can play that role. Among the ways to do that are to commission the system thoroughly and test it under real-world, worst-case scenarios. Failure to do either of these things due to budget concerns can lead to much greater expense in the long run.
Because data centers are often designed years before the facility is actually built out and populated with equipment, commissioning the UPS system can be especially crucial to confirming that it can actually hold the data center's load. Additionally, while most UPS manufacturers are diligent in their quality assurance, there's no guarantee that the contractor installed it properly or that it didn't get damaged in transit. As a UPS system design becomes more complex with additional levels of redundancy, it becomes more important to go beyond generic factory startup services and properly commission the system. An artificial load equal to ultimate data center design load is used to simulate the conditions under which the UPS will be expected to operate (called the load bank test). Because the load may vary from moment to moment (i.e., ramping up from idle first thing on a Monday morning, etc.), the tests should include step load testing for various scenarios that the UPS may be expected to accommodate without failure.
A UPS can fail in many ways: overload, battery failure, fan failure, overheating, EPO activation, etc. These are common failure modes that the UPS manufacturer has theoretically anticipated in its design, so don't be afraid to incorporate tests for worst-case scenarios. It's better to understand how a system will perform ahead of time in a controlled environment rather than guess what will happen when it's supporting a critical load. With redundant N+1 and 2(N+1) configurations, it is expected that if there is a fault in the system, the system will be able to automatically compensate for that failure. But with that additional redundancy also comes additional complexity, and associated test scripts should be expanded to account for additional possible failure scenarios. Having facilities personnel witness these tests is also an ideal way to get a head start on training
for when things go wrong.