IP ratings, standing for Ingress Protection ratings, are a standard defined by the International Electrotechnical Commission (IEC), specifically in IEC standard 60529. These ratings are used worldwide to classify and rate the degree of protection provided by mechanical casings and electrical enclosures against intrusion, dust, accidental contact, and water. For electromagnetic switches, as for any other electrical equipment, understanding the IP rating is crucial because it informs you about the environment in which the switch can safely operate.
An IP rating is typically composed of two digits:
- First Digit (Intrusion Protection): Indicates the level of protection that the enclosure provides against access to hazardous parts (e.g., electrical conductors, moving parts) and the ingress of solid foreign objects. This ranges from 0 (no protection) to 6 (dust tight).
| 0 | (or X – see section below): Not rated (or no rating supplied) for protection against ingress of this type. |
| 1 | Protection against solid objects larger than 50mm (accidental hand contact with open palm), but not against deliberate body contact. |
| 2 | Protection against solid objects larger than 12mm (accidental finger contact). |
| 3 | Protection against solid objects larger than 2.5mm (tools and wires). |
| 4 | Protection against solid objects larger than 1mm (fine tools and wires, nails, screws, larger insects and other potentially invasive small objects) |
| 5 | Partial protection against dust and other particulates, such that any ingress will not damage or impede the satisfactory performance of internal components. |
| 6 | Full protection against dust and other particulates, including a vacuum seal, tested against continuous airflow. |
- Second Digit (Moisture Protection): Indicates the level of protection against the ingress of water. This ranges from 0 (no protection) to 9K (protection against high-pressure, high-temperature water jets).
| 0 | (or X – see section below): Not rated (or no rating supplied) for protection against ingress of this type. |
| 1 | Protection against vertically falling droplets, such as condensation, sufficient that no damage or interrupted functioning of components will be incurred when an item is upright. |
| 2 | Protection against vertically dripping water when enclosure is tilted up to 15° off vertical. |
| 3 | Protection against direct moisture spray at angles up to 60° off vertical. |
| 4 | Protection against splashing water from any direction, tested for a minimum of 10 minutes with an oscillating spray (limited ingress permitted with no harmful effects). |
| 5 | Protection against low-pressure jets (6.3 mm) of directed water from any angle (limited ingress permitted with no harmful effects). |
| 6 | Protection against powerful jets (12.5 mm nozzle) of directed water from any direction. |
| 7 | Protection against full immersion for up to 30 minutes at depths between 15 cm and 1 metre (limited ingress permitted with no harmful effects). |
| 8 | Protection against extended immersion under higher pressure (i.e. greater depths). Precise parameters of this test will be set and advertised by the manufacturer and may include additional factors such as temperature fluctuations and flow rates, depending on equipment type. |
| 9K | Protection against high-pressure, high-temperature jet sprays, wash-downs or steam-cleaning procedures – this rating is most often seen in specific road vehicle applications (standard ISO 20653:2013 Road Vehicles – Degrees of protection). |
For electromagnetic switches, the appropriate IP rating would depend on where and how the switch is intended to be used. For example, a switch with an IP67 rating would be dust tight and protected against temporary immersion in water, making it suitable for outdoor applications or environments where it might be exposed to water. On the other hand, a switch with an IP54 rating would be protected against limited dust ingress and splashing water, suitable for indoor environments where heavy water ingress is not a concern but some level of dust and moisture resistance is beneficial.
Selecting a switch with an appropriate IP rating ensures that the switch can operate reliably under the conditions it will be exposed to, safeguarding both the switch’s functionality and longevity.