Improper cleaning

Improper cleaning means using unsuitable methods, such as mechanical removal or the wrong cleaning agents, which damage or strip the coatings on the module front glass. It is one cause of glass corrosion or abrasion, which reduces or removes the benefit of anti-reflective and anti-soiling coatings. In dry cleaning, small dust particles can scratch the glass and weaken the coating's optical properties, and the mechanical force of cleaning can damage the cells inside the module. In cleaning tests, reflectance changed a lot on several coated module types, which shows the anti-reflective coating was removed; nylon brushes and fine sand were more abrasive, and uncoated glass showed little or no effect. The risk is highest at desert plants, where frequent dry cleaning is needed and repeated cleaning wears the glass surface, reducing light transmission and module output. Active cleaning can wear down anti-reflective coatings and cause a small drop in efficiency, even though the immediate gain from cleaning is large. To reduce exposure, follow the module manufacturer's cleaning recommendations, use demineralized water with a mild approved detergent, stay below the maximum water pressure the manufacturer specifies (going over it can void the warranty), and use water close to the module temperature to avoid thermal shock. Before use, qualify a cleaning process with an accelerated test that uses the planned cleaning device, module type and expected soiling, and do not let anti-soiling coatings be damaged by unsuitable cleaning processes.

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• sentence 4: support check: partial - Strong reflectance deviations on several module types indicating ARC removal, nylon brushes and fine sand more abrasive, and uncoated glass unaffected are stated, but uncoated glass was tested without abrasive under brush pressure and the claim is simplified.
• sentence 5: support check: partial - Passages say desert plants need frequent (dry) cleaning and cleaning abrasion reduces transmittance and output, but do not state the risk is highest at desert plants as a comparison.
• sentence 7: support check: partial - Manufacturer recommendations, demineralized water with mild detergent, max pressure with warranty voiding, and water temperature close to module temperature are present, but the cleaning evidence for the detergent being 'approved' is fine while the combined 'to reduce exposure' framing and the truncated text leave minor gaps. -->