Honeywell 05701-A-0512 Rear Access Rack Assembly

The Honeywell 05701-A-0512, also cataloged as the 05701-A-0512 Rack Assembly, operates as a dedicated hardware component for mechanical slot protection and electrical bus routing within System 57 gas detection and industrial control networks. The subassembly functions as an 8-way structural chassis, establishing parallel backplane power and signal infrastructure to interconnect up to eight plug-in control or drive cards.

Hardware Specifications

Process Control and DCS Instrumentation

• 8-Way Backplane Signal Routing and Bus Integrity: The chassis features an integrated 8-way backplane printed circuit board that acts as a shared communication matrix. It routes parallel power rails and data signals across eight distinct slot keys, preserving uniform bus parameters and signal velocity without skewing transmission states between operational nodes.
• Rear Access Termination and Isolation Boundaries: The mechanical layout enforces strict physical separation via its rear access terminal blocks. Field sensor loops and power drops connect directly to the back of the rack framework, establishing clear fault boundaries that maximize channel-to-channel isolation metrics and prevent front-panel adjustments from exposing raw field electrical lines.

Frequently Asked Questions

Q: What is the main design difference between a rear access rack and a front access rack in the 05701 series?

A: The 05701-A-0512 rear access variant requires all field-side sensor lines, loop power feeds, and relay contacts to terminate at the back plane of the sub-rack assembly. This setup leaves the front panel completely unobstructed for card hot-swapping, diagnostic visual sweeps, and interrogation tool connections.

Q: Can an 8-way sub-rack be expanded to accommodate more than 8 control cards?

A: The physical frame configuration of this model is fixed at 8 slot positions. To expand channel capacity, supplementary 05701 series sub-racks must be mounted in tandem and interconnected via factory-specified high-density rib cables to bridge the parallel backplane buses.

Field Installation Guidelines

• Chassis Layout Alignment, Clearance Constraints, and Mechanical Seating: Bolt the 2.20 lbs chassis frame directly onto the standard cabinet mounting rails using specified rack screws. Check that the assembly is aligned square to prevent mechanical stress on the plug-in cards. Maintain a minimum 50 mm clearance perimeter above and below the rack boundaries to allow unrestricted vertical convective heat dissipation.
• Conductor Separation, Wireway Constraints, and Shield Grounding: Route all incoming field transmitter cables and DC power feeds into the rear terminals through separate low-voltage wireways isolated from high-current AC lines. Securely bond the structural metal chassis grounding stud to the primary enclosure copper earth bar using a heavy, low-resistance strap to shunt high-frequency switching noise safely away from the backplane lines.