When specifying industrial computing equipment, two rating systems describe environmental protection: IP (Ingress Protection) from the International Electrotechnical Commission (IEC) and NEMA ratings from the National Electrical Manufacturers Association. While related, these systems are not interchangeable.
IP Ratings Explained
IP ratings use a two-digit format: IP[dust][water]
First Digit: Solid Object Protection
| Rating | Protection |
|---|---|
| 0 | No protection |
| 1 | Objects >50mm |
| 2 | Objects >12.5mm (fingers) |
| 3 | Objects >2.5mm (tools, wires) |
| 4 | Objects >1mm (screws, ants) |
| 5 | Dust-protected (limited ingress) |
| 6 | Dust-tight (complete protection) |
Second Digit: Water Protection
| Rating | Protection |
|---|---|
| 0 | No protection |
| 1 | Vertical dripping water |
| 2 | Dripping water (15° tilt) |
| 3 | Spraying water (60° angle) |
| 4 | Splashing water (all directions) |
| 5 | Water jets (6.3mm nozzle) |
| 6 | Powerful water jets (12.5mm nozzle) |
| 7 | Temporary immersion (1m, 30 min) |
| 8 | Continuous immersion |
| 9K | High-pressure, high-temperature jets |
NEMA Ratings Explained
NEMA ratings are broader — they cover not just dust and water but also corrosion, ice, oil, and hazardous atmospheres:
| NEMA | Description | Approximate IP |
|---|---|---|
| 1 | Indoor, general purpose | IP20 |
| 4 | Outdoor, watertight | IP66 |
| 4X | 4 + corrosion resistant | IP66 |
| 6 | Temporary submersion | IP67 |
| 6P | Prolonged submersion | IP68 |
| 12 | Indoor, drip/dust-tight | IP52 |
| 13 | Indoor, oil/dust-tight | IP54 |
Key Differences
NEMA to IP works; IP to NEMA doesn't. A NEMA 4X enclosure meets IP66 requirements, but an IP66-rated enclosure doesn't necessarily meet NEMA 4X because NEMA also tests corrosion resistance.
NEMA includes environmental factors that IP doesn't: corrosion, ice formation, oil exposure, and gasket aging.
NEMA is North American, IP is international. Specify both for global deployments.
Choosing the Right Rating for Industrial Computers
| Environment | Recommended |
|---|---|
| Office/indoor | NEMA 1 / IP20 |
| Factory floor (dry) | NEMA 12 / IP52 |
| Factory floor (wet/oily) | NEMA 13 / IP54 |
| Outdoor temperate | NEMA 4 / IP66 |
| Outdoor marine/coastal | NEMA 4X / IP66 |
| Wash-down (food/pharma) | NEMA 4X / IP69K |
| Temporary submersion | NEMA 6 / IP67 |
Acnodes Corporation offers industrial computers and monitors rated to IP65, IP67, and IP69K with NEMA 4/4X enclosures. Contact us for help selecting the right protection level.