Low-quality material

Low-quality material means substandard materials used when PV parts are made, such as poor cable insulation or copper wire, low-grade connectors, weak junction box adhesives or backsheet films. For DC cables, low-quality insulation or copper wire is one of the main causes of cable defects, which can lead to overheating, insulation faults, ground faults and fire risk. For connectors, low-quality and faulty materials are common root causes of connector defects, along with poor installation and mismatched connectors, and a weak connection can cause ground faults, arcing and fires. A junction box can come loose if a low-quality adhesive is used; acrylic or PE foam tapes used in early years often lost their grip at low temperature. In modules, low-quality backsheet material, for example with low UV resistance, or backsheet and encapsulant materials that do not work together cause most premature degradation failures such as backsheet cracking. Inadequate encapsulant or backsheet materials can also cause loss of electrical insulation in the module. To reduce exposure, choose suitable materials and test that they are compatible before use, and replace damaged cable runs or connectors found during inspection.

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• sentence 1: support check: partial - Passages mention low quality cable insulation/copper, connectors, and junction box adhesive, but backsheet films are low-quality only in other text and 'low-grade connectors' is stated; the definition as a concept is implied, and backsheet low-quality material isn't in cited passages. -->