Full definition
Ingress Protection rating — a two-digit code defined by IEC 60529 that classifies the degree of protection provided by an electrical enclosure against the intrusion of solid objects (first digit, 0-6) and water (second digit, 0-9K). First digit: 0 (no protection), 1 (>50 mm objects), 2 (>12.5 mm — fingers), 3 (>2.5 mm — tools), 4 (>1 mm — wires), 5 (dust-protected — limited ingress), 6 (dust-tight — no ingress). Second digit: 0 (no protection), 1 (vertical drips), 2 (15° tilted drips), 3 (sprays to 60°), 4 (splashes from any direction), 5 (water jets — 6.3 mm nozzle, 12.5 L/min), 6 (powerful water jets — 12.5 mm, 100 L/min), 7 (temporary immersion — 1 m, 30 min), 8 (continuous immersion — depth/time specified by manufacturer), 9K (high-pressure hot water jets). Common industrial ratings: IP54 (dust-protected, splash-proof — indoor/sheltered outdoor), IP55 (dust-protected, water jets — outdoor), IP65 (dust-tight, water jets — washdown environments), IP66 (dust-tight, powerful jets — food/pharma), IP67 (dust-tight, temporary submersion — sensors, connectors). Rubber gaskets and seals are critical for achieving IP ratings — the enclosure seal design and material determine the IP level. Per IEC 60529 and EN 60529.