Power Systems requires clear attention to evidence that proves the system performs under realistic operating conditions. At advanced level, the note should be read as an integration check, not as an isolated equipment reminder. In a data center, a small weakness in this area can affect availability, safety, maintainability, or the confidence operators have during an abnormal event.
The field lesson is to verify the condition with more than one source where practical. Compare physical observations with logs, drawings, BMS or DCIM points, maintenance records, and the latest approved change information. If the evidence does not agree, record the gap and escalate it as an engineering uncertainty rather than forcing a quick conclusion.
Good evidence includes trends, event logs, field readings, change records, and confirmation from the systems that interact with this discipline. The note is intentionally concise: it does not create a universal limit or substitute for the applicable design, manufacturer instructions, local code, or site procedure. It gives the operations team a disciplined way to think about Power Systems before a small issue becomes a service-impacting problem.
