Mitsubishi BN624A96IG52A MELSECNET/H Fiber Optic Communication Module

The Mitsubishi BN624A96IG52A is a high-performance MELSECNET/H fiber optic communication module designed for Mitsubishi Q series programmable logic controllers. It provides high-speed, deterministic communication between PLCs, HMIs, and motion controllers over long distances using single-mode fiber optics. The module is essential for large-scale distributed control systems requiring high reliability and immunity to electromagnetic interference.

High-Speed Deterministic Communication

The BN624A96IG52A implements MELSECNET/H, a high-speed fieldbus protocol that uses token-passing mechanism to ensure deterministic communication. Each node in the network receives transmission rights within a fixed cycle, eliminating collisions and ensuring predictable communication latency—critical for multi-axis synchronization and emergency shutdown interlocking. The module operates at 10 Mbps full duplex over single-mode fiber with 1310 nm wavelength, achieving up to 30 km transmission distance without repeaters, sufficient to cover entire industrial parks or distributed facilities such as water treatment plants and pipeline monitoring stations.

Dual-Ring Redundancy for High Availability

The module supports dual-ring redundant topology where two fiber cables form a closed loop. If a fiber break occurs at any point, the network automatically reconfigures within 300 milliseconds, ensuring continuous control without interruption. This level of redundancy is essential for critical infrastructure such as subway signaling systems, chemical plants, and power generation facilities where downtime is unacceptable.

Application Domains

The BN624A96IG52A is used in steel mills (arc furnace control with EMI immunity), water treatment plants (distributed pumping station coordination), chemical plants (ESD interlocking across large areas), subway and railway signaling systems, and oil and gas pipelines (remote valve station monitoring). Its immunity to electromagnetic interference makes it particularly valuable in electrically noisy industrial environments.