Honeywell 12-SBUS SBUS Series

The Honeywell 12-SBUS, also cataloged as the 12-SBUS Rack-Mounted Chassis, operates as a dedicated hardware component for mechanical support and electrical backplane routing of active modules within SBUS network platforms.

Hardware Specifications

Process Control Integration and DCS Interface

• 4-20 mA HART Loop Protocol Pathing: The passive backplane bus integrated into the chassis routes multi-channel analog signals, maintaining clean shielding lines to prevent interference with parallel high-frequency HART communications.
• Channel-to-Channel Isolation Protection: Provides the physical structural separation necessary to isolate individual SBUS input/output modules, ensuring localized electrical faults on one card slot do not propagate through adjacent slots.
• Cold Junction Compensation (CJC) Stability: The heavy chrome-finished steel enclosure provides a thermally stable mass, reducing localized ambient temperature fluctuations across adjacent slots to preserve the accuracy of CJC calculations on installed thermocouple cards.

Frequently Asked Questions

Q: Does the 12-SBUS chassis backplane contain active microprocessors?

A: No. The backplane inside the 12-SBUS is completely passive. It contains no active microprocessors or logic gates, which increases system reliability by eliminating potential electronic failure points.

Q: Can modules be hot-swapped in this chassis?

A: The physical structural guides support sliding replacement, but hot-swap capability is strictly determined by the specific SBUS active module inserted into the slot. Consult the dynamic I/O card specifications before executing live extraction.

Q: How is backplane power distributed across the 12 slots?

A: Power is routed via heavy copper traces integrated into the backplane circuit board, supplied from redundant system power modules located in designated power slots.

Field Installation Guidelines

• Grounding Straps: Prior to mounting the chassis into a 19-inch cabinet, connect the dedicated copper grounding bolt located at the rear of the steel frame to the primary cabinet ground bus bar.
• Airflow Clearances: To maintain passive convection cooling, ensure a minimum of 50 mm clearance is preserved above and below the chassis assembly inside the enclosure.
• Cable Routing: Secure all field signal wiring using the integrated front cable guides. Avoid routing low-voltage SBUS signal lines in parallel with heavy AC power distribution cables in the same wire duct.