Wireless communication promises great potential for optimizing operations in process plants, but at the same time the relevant explosion protection regulations must be observed in the potentially explosive atmospheres present here. The integration of wireless access points in Ex-certified enclosures provides a cost-efficient, reliable, and secure communication solution that meets the strict requirements of hazardous area standards. Pepperl+Fuchs offers wireless access point solutions that are fully certified according to ATEX/IECEx standards and provide the basis for continuous wireless communication in Zone 2 using Ex nR technology as well as Ex d certified access point solutions for Zone 1/21 hazardous areas. Read on and find out more about both certifications in this blog article.

What Does It Mean When Enclosures Have an Ex nR or Ex d Certificate?

Ex nR certified, or restrictive breathing, enclosures (acc. to standard IEC 60079‐15) for Zone 2 hazardous areas eliminate the risk of explosion by preventing flammable gases from entering the internal enclosure. This technique ensures that potentially explosive gases do not come into contact with hot surfaces or ignition sources within the enclosure. The certification is exclusively for Zone 2 applications.

Ex d certified “flameproof” enclosures (acc. to standard IEC 60079-1) for Zone 1/21 allow an explosion of flammable gases or vapors to occur inside them due to electrical equipment. However, the enclosure is designed to withstand, contain and cool this explosion, preventing the surrounding atmosphere from also being ignited.

What Are Explosion-Protected Wireless Access Point Solutions?

There are two different types of solutions to operate standard industrial Wi-Fi® access points in hazardous areas:  Ex nR-based solutions for Zone 2 and Ex d-based solutions for Zone 1/21.

Ex nR-based solutions for Zone 2

A combination of lightweight and flexible yet equally rugged glass-fiber reinforced plastic (GRP) or stainless steel enclosures from the Pepperl+Fuchs GR and SR series is used for this reason—while the tightly sealed main housing, which is designed with restricted breathing type of protection “Ex nR” contains the actual Wi-Fi access point (Cisco MR 46 or Aruba AP-535 as standard), the Ex ec certified enclosure underneath accommodates the cabling and an Ex e certified patch panel, which is required for the Ethernet connection. This separates the Zone 2 wireless access point solution pragmatically into two functional units, minimizing the maintenance efforts required: The Ex nR ignition protection of the access point main enclosure remains unaffected from cabling work in the lower enclosure and does not need to be retested. In the GRP version, the radio signals penetrate the enclosure without the need for external antennas, while the SR stainless steel enclosure is equipped with Ex-certified antennas to distribute the signals in the best possible way. Depending on further requirements, customer-specific configurations with other industrial wireless routers and access points can also be implemented as an alternative to standard solutions with Cisco MR 46 or ARUBA AP-535 that are available at short notice.

Ex d-based solutions for Zone 1/21

If the wireless network is also to be installed in potentially explosive areas of ATEX/IECEx Zone 1/21, Pepperl+Fuchs also manufactures customer-specific access point solutions in the flameproof enclosure type of protection “Ex d”. Depending on the specification, various numbers of Ex-certified wireless antennas can be attached to the robust cast aluminum housing in order to achieve optimum coverage and range of the network within the process plant. In addition to wireless access points, it is also possible to install other radio frequency equipment such as RFID read/write devices, UWB receivers, or LoRaWAN gateways in these enclosure solutions for Zone 1/21.

What Are the Advantages of Ex-Certified Wireless Access Points Solutions?

Integrating Ex nR and Ex d protected enclosures with wireless access points offers numerous benefits for process industry applications:

They ensure seamless connectivity: Wireless access points provide reliable wireless communication for remote monitoring and control, reducing the need for wired infrastructure in hazardous areas. Workers can access critical information and communicate effectively without compromising explosion protection.

The provide advanced security measures: Security is critical, especially in process industry environments where sensitive data is transmitted wirelessly. Protected wireless access points can make use of encryption protocols such as WPA2 or WPA3 to protect data integrity and prevent unauthorized access. Due to the flexibility of Pepperl+Fuchs certificates, customers can use their standard Wi-Fi access points that they use in their company, which is an important advantage.

They improve safety: By complying with Ex d (IEC 60079-1) and Ex nR (IEC 60079-15) standards and offering IP66 or IP66/IP67, and NEMA Type 4X degree of protection, the integrated solution eliminates the risk of ignition by sealing all components, ensuring the safety of personnel and assets in hazardous environments.

They are a lightweight and cost-effective solution: The long-term reliability and durability of the lightweight GR and SR series enclosures with Ex-certified access points minimize maintenance costs and downtime.

Ex-Protected Enclosures Can Be Integrated with Other Wireless Technologies

GR and SR series enclosures with Ex d and Ex nR certificate offer robust protection in explosive atmospheres, making them essential for hazardous environments. Integrating these enclosures with wireless technologies such as LoRaWAN, RFID read/write devices, Bluetooth, and cellular networks provides additional safety and efficiency in industrial settings.

LoRaWAN, for example, enables long-range communication, which is ideal for monitoring remote assets in hazardous areas. By installing LoRaWAN gateways within Ex-protected enclosures, data can be transmitted securely over extended distances without compromising safety. RFID read/write devices facilitate asset tracking and identification. By housing RFID read/write devices in protected enclosures, companies can accurately monitor inventory and equipment in hazardous areas.

Integrating Bluetooth modules within enclosures allows for seamless short-range communication between devices in hazardous areas. Cellular networks, on the other hand, provide reliable connectivity for remote monitoring and control. Cellular routers and modems enable connectivity in hazardous location enclosures, allowing for remote monitoring, control, and data transmission in environments where traditional wired connections are impractical or dangerous.

An End-to-End Solution through to the Intrinsically Safe Wireless End Device

As soon as the network has been established in the process plant using the Ex-certified wireless access points, mobile workers can use the intrinsically safe mobile end devices (Ex i in accordance with IEC 60079-11) from the Pepperl+Fuchs brand ecom throughout hazardous areas. These include the rugged industrial tablet thin client with Pepperl+Fuchs RM Shell firmware for location-independent access to process data and the intrinsically safe Android® Smart-Ex® smartphone, which allows service technicians to stay in touch with the control room via Voice over IP. With this combination of wireless access points and intrinsically safe mobile devices, Pepperl+Fuchs covers all wireless communication applications in large process plants with hazardous areas.

More Information

• Wireless Access Point Ex nR enclosure solution: GR.RER*
• Wireless Access Point Ex d enclosure solution: EJB10A.I.CP-Y*
• Wireless Access Point Ex d enclosure solution: GUB3L.I.CP-Y*