1788-FBJB6 Allen-Bradley FOUNDATION Fieldbus 6-Port Junction Box

Product Description

The 1788-FBJB6 serves as a high-reliability distribution node for H1 segment networking. Engineered by Allen-Bradley, this junction box facilitates the integration of up to six field instruments within a process control architecture. It is designed to maintain signal integrity across long-run trunk lines while providing branched connectivity for localized device clusters.

This module supports both FOUNDATION Fieldbus and PROFIBUS PA physical layers, adhering to the IEC 61158-2 standard. The open-style construction is optimized for cabinet installation, utilizing a compact footprint to maximize rail space. With a current consumption of only 40 mA, it minimizes the overall power budget of the fieldbus segment.

Technical Specifications

• Manufacturer: Allen-Bradley / Rockwell Automation

• Model Designation: 1788-FBJB6

• Network Compatibility: FOUNDATION Fieldbus (H1) and PROFIBUS PA

• Device Capacity: 6 H1 Media Drops (Spurs)

• Trunk Interfaces: 1 Port Input / 1 Port Output (Daisy-chain capable)

• Operating Voltage Range: 12 to 32V DC

• Internal Current Draw: 40 mA @ 24V DC

• Mounting Infrastructure: Standard 35mm DIN Rail

• Physical Housing: Open-style (IP00 rated)

• Wiring Torque Specifications: 0.5 to 0.6 Nm (4.4 to 5.3 lb-in)

• Mechanical Shock Rating: 15 G (Operating)

• Net Weight: 0.34 kg (0.75 lbs)

• Isolation: Non-isolated (Common ground architecture)

Implementation FAQ

Does the 1788-FBJB6 include integrated bus termination?The 1788-FBJB6 provides the physical connection points for a segment but typically requires an external terminator if it is located at the end of the trunk line. Always verify segment impedance during commissioning.

Can this unit be used in hazardous areas?As an open-style device, it must be installed within a secondary enclosure (NEMA 4X or IP66) that meets the specific hazardous location ratings (Class/Division or ATEX) required for the environment.

Is it compatible with different cable types?Yes, it accepts standard Type A fieldbus shielded twisted-pair cabling. Ensure the terminal torque is strictly followed to prevent signal intermittent issues in high-vibration environments.