Why a visual inspection still matters
Thermal and electroluminescence inspections reveal faults that cannot be seen, which makes it easy to overlook the faults that can. Many problems on a commercial array are visible: broken glass, loose wiring, shading from vegetation, animal damage, corrosion, soiling patterns and mounting hardware that has moved. They are also the problems that show up in the field soonest after a storm. A visual inspection is the foundation that the other methods build on.
Start with a plan and the as-built
An inspection without a map produces findings nobody can find again. Before the visit, obtain the as-built layout showing arrays, rows, strings and module positions. Agree on a numbering scheme so that every finding has an address, such as array, row and module position. Decide what condition categories you will use, so findings can be counted and ranked.
Modules
- Glass. Cracks, chips, shattered corners and impact marks.
- Frames. Bent or corroded frames and damaged corners.
- Laminate and backsheet. Delamination, bubbling, yellowing, browning or burn marks.
- Cells and busbars. Snail trails, discoloration and visible cell damage.
- Junction boxes. Cracked, loose or discolored boxes and cable entries.
- Labels. Missing or unreadable nameplates, which matter for warranty and replacement.
Mounting and structure
- Racking. Bent, corroded or displaced rails, and rows that no longer line up.
- Fasteners and clamps. Missing, loose or corroded hardware.
- Ballast. On ballasted roofs, blocks that have shifted, cracked or gone missing.
- Penetrations and flashings. Signs of leaks or damage around attachments, which tie into the roof membrane and warranty context.
Wiring, grounding and enclosures
- Cable management. Sagging, chafed, pinched or unsupported conductors and exposed connectors.
- Connectors. Discoloration, melting or disconnected plugs.
- Grounding. Missing or loose bonding jumpers and corroded lugs.
- Combiners, disconnects and inverters. Enclosure damage, water ingress, labels, warning signs and clear working space.
Surroundings
- Soiling. Dirt, bird droppings and film, noting whether the pattern is uniform or localized.
- Vegetation. Growth that shades modules or crowds equipment, especially on ground-mount and carport sites.
- Animals. Nesting, chewed cables and droppings.
- Roof or ground condition. Ponding, erosion, drainage and access paths.
- Fencing and signage where applicable.
How to record findings
Each finding should include the location, a category, a severity, and at least one photograph that shows the problem and its surroundings. A close-up of the defect plus a wider shot that lets someone find it again is the habit that pays off. Use consistent categories so the results can be tallied across the site and compared with the next inspection.
Rank by consequence
Broken glass and exposed conductors are safety issues. Loose hardware may be a structural or wind issue. Soiling is a performance issue. A short ranking at the top of the report tells the owner what to act on first.
How a visual pass fits with other inspections
Visual inspection finds what is visible on the surface. It does not find hot cells that look normal or cell cracks beneath intact glass. That is why it is usually paired with infrared and, where the question is cell damage, EL, as the note on thermal scan versus EL test explains. The infrared inspection interval can be matched to the visual schedule so that each visit has a clear purpose.
If the array was built from a site survey, the original record helps: the commercial rooftop survey checklist describes the conditions captured before construction, which are a useful comparison when you inspect later.
Preparing for the visit
- Obtain the as-built layout and agree on a module numbering scheme.
- Confirm roof or site access, fall protection requirements and who escorts the crew.
- Schedule in good light, and avoid wet conditions on the roof.
- Decide in advance how findings will be categorized and ranked.
- Agree how the owner wants to receive the report and photographs.
It also helps to bring the previous inspection report, if there is one, so that the crew can confirm whether earlier findings were repaired and whether new damage has appeared since. A repeat visit that compares against the last record is far more informative than a fresh list with no history, and it lets the owner see whether the condition of the array is stable, improving or getting worse over time.
Where Solar Survey AI fits
Our visual inspection service delivers full-array imagery at module resolution, recording soiling, physical damage, vegetation encroachment and mounting failures and locating them against the as-built. Send us the layout and the question you need answered, and we will scope the inspection.