An enclosure protection rating tells you how well a housing keeps out solid objects and water. It is given either as an IEC IP code or as a NEMA enclosure type. In an IP code, the first digit covers protection against solid objects and dust, from non-protected up to dust tight. The second digit covers protection against moisture, from non-protected up to submersion. For example, IP65 means dust tight and protected against water jets. IP54 means interior dust deposits and splashing water from any direction are kept out. Under IEC 60529, a rating also covers all lower levels, up to water numeral 6. An enclosure rated only 7 or 8 is not considered suitable for water jets unless it is dual coded. NEMA types can be converted to IP equivalents, but not the other way round. NEMA adds tests that IEC does not require, such as corrosion, gasket aging and external icing. PV and storage equipment datasheets list these ratings, for example NEMA 4X on string inverters and NEMA 3R or IP54 on battery and power-conversion equipment. On site, the installer has to keep the enclosure rating intact. One inverter manual says that losing the NEMA 4X rating voids the warranty.
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related_toc1 drafted · lead IEC 60529 proposed
IEC 60529 defines the IP code; a rating at a given numeral also implies compliance with all lower numerals, for the water digit up to 6.
tbl=44.r10 h=b78a71310257tbl=90.r12 h=b1ebf310652ftbl=47.r13 h=9792455e2b87sec=h227 h=16bb690c871esec=h226 h=3cfbf1a84eb1c2 drafted · lead NEMA 250 proposed
NEMA Publication 250 is the source for converting NEMA enclosure types to IP designations; the conversion only works in one direction.
sec=h226 h=3cfbf1a84eb1c3 drafted · lead Sunny Boy Smart Energy US-50
Electronics are rated IP65 per IEC 60529.
tbl=47.r13 h=9792455e2b87c4 drafted · lead Sunny Island 4.4M / 6.0H / 8.0H
Rated IP54 per IEC 60529.