Open or detached junction box

This signature is found by looking at the module rear: the junction box lid is open or loose, or the whole box has shifted or come away from the backsheet. The adhesive or sealant that holds the box to the backsheet may look weathered or yellowed. Seals at the wire entry or lid may be squeezed, broken, brittle or missing. The housing itself may also be weathered, brittle, cracked, warped, melted or burned. Visual inspection is the usual way to find junction box failures. An infrared camera can show higher resistance or mismatch inside the box as a hot junction box. Detachment comes from poor fixing to the backsheet or low-quality adhesive. Early acrylic or PE foam tapes often lost their grip at low temperature. A box can also open or work loose because of poor manufacturing, internal air pressure at high temperature when the box has no exhaust path, delamination near the box, or rough handling and short or unfixed cables during mounting. An open or detached box lets humidity in, which corrodes the interconnections. This causes junction box interconnection failure, performance loss, and a higher risk of arcing and fire. A loose box also puts mechanical stress on its internal contacts, which can break them and expose live parts, so treat it as a safety hazard.

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• sentence 8: support check: partial - Mechanical stress, breaking contacts and exposing persons to live components are stated, but the instruction to treat it as a safety hazard is only loosely supported (high severity, safety issues). -->