TRICONEX 3902AX Universal I/O Card: An Integrated Solution for High Density and High Security
In the field of industrial automation and safety control, especially in process industries involving flammable and explosive environments, reliable, efficient, and safe I/O systems are crucial. TRICONEX 3902AX Universal Input/Output Card, as Schneider Electric EcoStruxure ™ Triconex ™ As a member of the safety system family, with its flexible design and high integration, it has become one of the core components for building high reliability safety instrumented systems (SIS) and emergency shutdown systems (ESD). Perfectly matched with it is Pepperl+Fuchs' customized H-System intrinsic safety isolation barrier and terminal board solution for the Tricon CX system, which together brings industry-leading safety assurance and space efficiency to users.
Product Overview: Flexible and Universal High Performance I/O Card
The TRICONEX 3902AX (and its sister series 3902X) is a 16 channel universal input/output card. Its "universal" feature is reflected in the processing capability of a single card supporting multiple signal types, including analog input (AI), analog output (AO), digital input (DI), and digital output (DO). This design greatly improves the flexibility of system configuration, reduces the types of cards and spare parts inventory, and simplifies system design and maintenance work. This card is designed specifically for the Tricon CX platform and is an ideal choice for building compact, high channel safety control cabinets.
Core technological advantage: combination of high density and high security
The 3902AX card itself has the typical high reliability and fault tolerance of the Tricon system. However, in hazardous location applications, safety isolation must be carried out between on-site instruments and control systems to prevent energy from entering the hazardous area and causing explosions. This is where Pepperl+Fuchs H-System plays a crucial role.
Pepperl+Fuchs, as a technology partner of Schneider Electric for over thirty years, has set the industry benchmark for its H-System for intrinsic safety solutions. Customized terminal boards of HICTB16-TRX-RAC-PL-IO model can be used in conjunction with the TRICONEX 3902AX. This terminal board is pre integrated with dedicated ELCO or D-Sub connectors suitable for the Tricon CX system, enabling plug and play connection with 3902AX cards, greatly simplifying cabinet layout and wiring work.
On the terminal board, various H-System intrinsic safety isolation barrier modules can be installed, such as:
HIC2441: Universal module (supporting AI/AO/DI/DO), suitable for SIL 2 safety level applications.
HIC2025AI and HIC2025Y1AI: isolation gates designed specifically for analog input, also meeting SIL 2 requirements.
These HiC modules have a width of only 12.5 millimeters and are installed in a unique "plug lock" style, which allows them to be securely mounted on the terminal board without the need for any tools or additional wiring. This design achieves the highest signal density on the market, effectively solving the problem of tight control cabinet space. At the same time, the low-power design of the module reduces heat accumulation inside the cabinet and improves the overall operational stability of the system.

Complete system integration and authentication assurance
Pepperl+Fuchs H-System for Tricon CX is a fully tested and validated solution. Its cooperation with TRICONEX 3902AX ensures the integrity and safety of signal transmission from the hazardous area on site to the safe area of the control system. This solution has relevant certifications worldwide, providing users with a unified and reliable security barrier solution deployed in global projects.
In addition to being compatible with the latest Tricon CX system, Pepperl+Fuchs also offers customized terminal board solutions for the previous generation Tricon system and Foxboro DCS, protecting users' existing investments and ensuring technological continuity.
Widely applicable scenarios
The TRICONEX 3902AX, in conjunction with the H-System intrinsic safety solution, is widely applicable in industries that require extremely high safety and reliability, including:
Oil and gas extraction and refining
Chemical and Pharmaceutical Industry
energy and electricity
Oil and gas pipeline transportation
Other process industries with potential explosive environments
In these scenarios, the system is used to perform critical safety functions such as emergency shutdown, fire and gas detection and protection, process shutdown interlocking, etc. Its performance directly affects the safety of personnel, equipment, and the environment.



