IP Protection Ratings: A Guide to Industrial HMI Selection

In the world of industrial automation, the resistance of devices to dust, liquids and other external agents is not a detail but a necessity. The choice of a human-machine interface (HMI) suitable for the operating environment inevitably passes through the correct interpretation of IP degrees of protection.

But what do the acronyms IP66, IP67, IP69K really mean? In this article we shed light, providing a comprehensive and reliable overview to help professionals and technicians in selecting the most suitable solution.

What are IP ratings

The IP (International Protection)rating system is defined by the IEC 60529 standard and indicates the level of protection an electrical enclosure offers against:

• the penetration of solids (dust, sand, metal particles)
• ingress of liquids, including splashes, water jets or immersion.

The code consists of two digits:

• First digit (0 to 6) → Protection against solids.
• Second digit (0 to 9) → Protection against liquids

Some devices also carry an additional letter (e.g., "K" in IP69K) to indicate specific protection, such as against high-pressure and temperature washdowns.

Practical examples and industrial applications

The following are some of the most common examples in the industrial sector:

• IP65: Providestotal protection against dust. Withstands water jets from any direction. It is considered the ideal degree of protection for production environments with occasional exposure to water.
• IP66 : Has thesame level of dust protection, but with resistance to more powerful water jets. It turns out to be a suitable choice for outdoor installations or intensive industrial environments.
• IP67 : In addition to total dust protection, it withstands temporary immersion in water (up to 1 meter depth for 30 minutes). It is the most suitable IP rating for devices near liquids or in mobile applications.
• IP69K: Synonymous with thehighest level of protection: immersion, dust and high-pressure washing (up to 80°C and 100 bar). It is considered indispensable in the food and pharmaceutical industry or in environments requiring frequent sanitization.
  
  

Why it is important to choose the right IP rating

Underestimating the degree of protection can lead to significant damage including:

• Downtime caused by seepage;
• Reduced useful life of devices;
• Operatorsafety hazards;
• High costs for maintenance and replacement.

Conversely, choosing a device with the correct IP rating ensures reliability over time, protection from challenging environmental conditions, and optimization of performance and productivity.

For ease of understanding and choice, below is a summary table with all IP grades, their definitions and application contexts, useful for those designing, purchasing or installing HMI systems in industrial settings.

Comparison table: which IP grade to choose based on the application?

The table below compares the most widely used IP grades in industry, highlighting key criteria for choosing the most suitable device for your operating environment.

More precise details are recommended on official normative reference sites.

FAQ: quick answers to common doubts about IP ratings

When choosing an industrial HMI device, IP ratings often generate interpretative doubts. Below we answer the most frequently asked questions to help you make more informed decisions.

Is IP69K "more protected" or is it "better" than IP67?
Not necessarily. IP69K is designed to withstand high-pressure, high-temperature washdowns typical of the food, pharma and chemical industries.
IP67, on the other hand, provides sealing under temporary immersion, which is useful for wet or flood-prone environments. These are not "in order of value," but of context of use.

What is the difference between IP and IK?
No. IP measures protection against the ingress of solids and liquids while IK measures resistance to mechanical shocks such as blows or vibrations.

Is a higher IP rating always better?
Only if required by the operating environment. A high IP can result in higher costs that are not justified in non-critical environments.

Can I use an IP65 HMI outdoors?
Only in moderately protected environments. An IP65 rating does not guarantee sealing in heavy rain or heavy washing. For outdoor or harsh environments, at least IP66 or higher is recommended.

Choosing the right IP rating is not just a technical matter-it means investing in safety, operational continuity, and durability. Understanding the different levels of protection allows you to select the right HMI interface for your environment, avoiding unexpected costs and ensuring reliable performance.

Exor International designs and manufactures HMI interfaces designed to provide maximum protection and operational continuity in even the most demanding environments.