What is IP rating? IP-rated cables for harsh environments

1.1 What is a harsh environment?

A harsh environment can include various conditions that may cause significant damage to electrical systems if they are not properly designed. Environmental factors such as extreme high or low temperatures, sudden temperature fluctuations, dust, humidity, moisture, and even salt mist can have a major impact. Additionally, real-world application factors may include vibration, impact, high pressure, corrosive chemicals, and different types of electrical stress.

Even when equipment is housed in a fully sealed enclosure, cable connectors can still be entry points for dust, moisture, or other contaminants, leading to damage to internal components. Therefore, selecting the right cables and cable accessories that can withstand harsh environments is crucial.

1.2 Impacts of harsh environments on electrical systems

• Extreme temperatures: Most failures in electronic equipment due to environmental factors result from excessively high or low temperatures, as well as sudden temperature fluctuations. These conditions create thermal stress due to differences in the thermal expansion coefficients of various materials.
• Vibration and impact: Vibration and impact are unavoidable in many harsh environments, such as in the transportation industry or industrial machinery. These forces can cause cracks in solder joints, loosening of screws, or the failure of assembled components.
• Explosion risk: Industries such as oil and gas, coal mining, and wood processing facilities often have environments filled with highly flammable materials like gases, vapors, dust, or fine powders. In such conditions, even a small spark can trigger a serious explosion.
• Chemical corrosion: In many harsh environments, high humidity combined with salt mist is a common cause of connector corrosion. Additionally, exposure to industrial chemicals such as acids (sulfuric, chromic, acetic, hydrochloric, hydrofluoric acids) or bases (ammonium, potassium, sodium hydroxides) can severely damage electronic components and connectors. Therefore, selecting corrosion-resistant materials and fully sealed designs is crucial in these environments.

2.1 Meaning of the IP rating

The IP (Ingress Protection) rating system uses a two-digit code to define a product’s level of protection against the intrusion of solid particles (such as dust) and liquids (such as water). The appropriate IP rating for a product depends on the level of exposure to dust or water during operation. To ensure reliability, it is essential to select an IP rating that can withstand the worst possible conditions the equipment might encounter.

IP ratings are defined by the IEC 60529 standard, which evaluates the protection level of enclosures (including connectors) against dust and liquid ingress. This standard is also recognized in the European Union (EU) under the designation EN 60529.

The IP rating consists of two digits:

• The first digit: Indicates the level of protection against solid objects and dust.
• The second digit: Indicates the level of protection against water and other liquids.

IP ratings cover a range of protection levels, from resistance to water splashes to the ability to withstand prolonged submersion. Components and equipment with higher waterproof ratings typically also offer better dust protection.

When selecting electrical cables and connectors with an IP rating, the first step is to assess the worst-case exposure to dust and moisture that the product might encounter. Additionally, some environments have unique factors that must be considered when designing cable connectors, depending on the substances the system may come into contact with.

Below are some common environments where IP-rated cables and accessories are required:

3.1 Marine environment

Electrical cables used in offshore applications or aboard ships should have a minimum IP64 rating to prevent water spray from penetrating and causing moisture-related damage. However, for better protection, IP67-rated products are recommended, ensuring resistance to temporary submersion in shallow water.

For marine environments where equipment might be submerged for extended periods, IP68-rated products are the ideal choice, as they ensure the device remains operational even after being retrieved from deep water without water ingress.

3.2 Industrial environments

Depending on the type of equipment used in industrial environments, electrical cables and connectors with an IP65 rating or higher are necessary. This ensures protection against high-pressure water jets from multiple directions, even though full submersion resistance may not always be required.

Additionally, IP65-rated connectors typically offer excellent dust protection, which is crucial in factories and manufacturing environments where airborne dust and contaminants are common.

3.3 Outdoor electrical equipment

Most outdoor electrical equipment requires a minimum IP65 rating to ensure stable operation. Two common examples include: lighting systems and security devices. For higher durability and reliability, IP66 or IP67-rated products are the optimal choice, as they provide enhanced protection against harsh weather conditions.

4.3 IP68-rated cable connectors

In addition to IP68-rated cables and cable glands, HELUKABEL’s HELUTEC® cable connectors are designed to resist water jets and temporary submersion. Each cable assembly, including the connector and cable, meets IP66/IP67 standards. For special applications, such as environments exposed to water or steam, these connectors can be certified up to IP69K.

The HELUTEC® 615/915 series is specifically designed for long-term underwater operation. Testing has shown that even after continuous submersion for 120 hours at a depth of 15 meters under 1.5 bar pressure, these connectors continue to function normally. As a result, both series are IP68-certified for maximum protection in harsh conditions.