For any operational issue we encounter as asset managers, the first order of business is to re-energize the equipment and restore production as quickly as possible. But once the site is back online, the work is far from over. Understanding why the fault occurred, and what it takes to prevent a recurrence, is just as important as the recovery itself. A recent event at one of our sites brought this into sharp focus and offered a valuable lesson in operational readiness.
We engaged an engineering firm to conduct a formal root cause analysis on one of these events. Their first request was straightforward: provide data from the site’s SEL 735 Power Quality Meter and SEL 751 Feeder Protection Relay. These devices continuously log power quality metrics, load data, and event histories, and that information would be essential to understanding what preceded the fault and what triggered the failure.
The Data Was There. Accessing It Was Not Simple.
The meters and relays had been logging data as designed. The problem was that our team did not have a clear, documented process for extracting and interpreting that data on demand. Accessing the SEL portal, pulling the right logs, and getting the data into a format the engineers could work with required more time and effort than it should have. During an active investigation, that friction matters. Every delay in delivering data to the root cause team is a delay in getting answers.
This experience made clear that having equipment in place is not the same as being prepared to use it. The gap between the two is operational readiness, and it showed up at exactly the wrong moment.
What Good Data Access Looks Like
A well-prepared asset management program treats data access as infrastructure, not an afterthought. For protection and metering equipment like SEL devices, that means having documented procedures for accessing device portals and software tools, knowing which logs to pull and how far back they are retained, maintaining up-to-date login credentials and vendor relationships, and ensuring that at least one member of the operations team has hands-on familiarity with the process before it is needed urgently.
This is not limited to SEL equipment. Every site has multiple systems generating data that could be critical during an investigation: inverter event logs, SCADA data, production meters, weather stations, and protection relays from various manufacturers. The ability to retrieve that data quickly and accurately should be a standard expectation, not an ad hoc effort.
The Broader Lesson for Solar Owners
Root cause analysis is only as good as the data that feeds it. Engineering firms and technical experts can do excellent work when they have complete, timely information. When data is missing, delayed, or requires significant effort to retrieve, investigations take longer, conclusions are less certain, and the risk of a repeat failure increases.
For owners and operators managing a fleet of solar assets, this points to a clear operational priority: build and maintain a site data inventory. Document what systems are logging data at each site, how to access them, and who is responsible for retrieval. Establish vendor relationships proactively, including registration with manufacturer portals and service platforms, so that when an event occurs the process is already in place.
Equipment failures are inevitable in a long-lived asset class. Being prepared to learn from them quickly is a choice, and it is one that pays dividends in reduced downtime, better-informed maintenance decisions, and a stronger overall understanding of fleet health.
