What does IP ratings means for power supplies?


The IP rating denotes the level of protection an electrical device has against the ingress of foreign objects and moisture. This article explores the various IP codes, their distinctions, and considerations to bear in mind when selecting a power supply.

Environmental factors such as dust or moisture can hinder the proper functioning of electrical components within a power supply. Additionally, safeguarding the interior of the power supply against intrusion by foreign objects, such as tools, screws, wires, and accidental user contact, is crucial. Particularly when power supplies are installed outdoors, attention to the International Protection (IP) code is vital for safe usage and to mitigate costly downtime.

What are the IP codes?

IP codes typically consist of the abbreviation IP (International Protection or Ingress Protection) followed by two digits (e.g., IP20, IP54, IP67, etc.).

The first digit denotes protection against accidental contact and the ingress of foreign objects, such as sand and dust, into the device. The second digit indicates protection against water and moisture.

For industrial power supplies, the relevant standard for determining the IP rating is DIN EN 60529. ISO 20653:2013 is also commonly used for road vehicles, specifically for electrical components needing additional protection against pressure washing, such as with a steam cleaner.

In the context of power supplies, IP codes are sometimes conflated with protection classes. While IP codes pertain to the intrusion of foreign objects and water, as well as accidental contact, International Electrotechnical Commission (IEC) protection (or appliance) classes determine the structure and insulation of power supplies to shield users from electric shocks.

The following table provides an overview of the significance of the numbers within different IP ratings:

Foreign objects


No protection


Protected against solid foreign objects with a diameter ≥ 50 mm (e.g. a hand)


Protected against solid foreign objects with a diameter ≥ 12 mm (e.g. a finger)


Protected against solid foreign objects with a diameter ≥ 2.5 mm (e.g. a tool)


Protected against solid foreign objects with a diameter ≥ 1 mm (e.g. wires)


Complete protection against contact and dust


Complete protection against contact and fully dust-tight




No protection


Protected against vertically dripping water


Protected against vertically dripping water when the enclosure is tilted (up to 15°)


Protected against water falling as a spray at an angle up to 60° from the vertical on both sides


Protected against water splashing from any direction


Protected against water jets from any direction


Protected against powerful water jets from any direction


Protected against temporary immersion


Protected against continuous immersion


Protected against high-pressure, high-temperature water jets


Which IP ratings are commonly assigned to industrial power supplies?

The required IP rating varies depending on the installation site and prevailing environmental conditions. Typically, manufacturers of power supplies stocked for immediate delivery offer products with specific IP ratings that have become industry standards. The following table provides an overview of the prevalent IP ratings for industrial power supplies.

For unique requirements necessitating different combinations of protection against contact and moisture, customized power supplies tailored to customer specifications often present the optimal solution.


What do codes like IPX4 and IP6X signify?

Electrical devices are frequently assessed concerning only one of the two codes for protection against foreign objects and water.

The “X” denotes that the product has not undergone the relevant tests for that specific code. Thus, it’s not a variable that can be substituted with any value from the IP ratings table.

A power supply labeled IP6X assures complete protection against contact and is dust-tight but hasn’t undergone testing for water intrusion. Similarly, a power supply bearing the IPX4 code has been evaluated for water splashing but not for the infiltration of foreign objects.

In essence, the IP rating delineates the level of protection a device offers against inadvertent contact, foreign objects, and liquids. Typically comprising two digits, the first digit signifies defense against accidental contact and foreign objects, while the second denotes resistance to water and moisture. Higher numbers correspond to superior protection levels. Industrial power supplies housed within cabinets typically bear an IP20 rating, whereas those positioned outside protective environments necessitate higher ratings, such as IP54 or IP67.