Allen-Bradley 1746-A10/B SLC 500 I/O Chassis

Configured for mechanical housing and backplane electrical distribution in SLC 500 modular systems, the Allen-Bradley 1746-A10/B (1746-A10/B PLC rack) provides direct physical/electrical execution for module interconnection across SLC 500 distributed control architectures.

Within the chassis backplane, the unit routes 5 VDC and 24 VDC distribution rails to installed I/O and communication modules while maintaining slot-to-slot signal alignment via the SLC 500 backplane bus structure.

Hardware Specifications

SLC 500 Backplane Distribution Characteristics

The 1746-A10/B chassis implements SLC 500 backplane bus distribution for synchronized module communication and power routing. The 5 VDC and 24 VDC rails are segmented across the backplane to support mixed module populations including analog, digital, and communication cards. Slot addressing is managed via mechanical keying and backplane signal lanes, ensuring deterministic module enumeration during controller scan cycles.

Frequently Asked Questions (FAQ)

Q: Can modules be inserted or removed while the chassis is powered (RIUP behavior)?
A: RIUP support depends on installed module type. Backplane voltage remains present; insertion/removal is constrained by module-specific electrical isolation design and system configuration.

Q: What is the backplane current limitation across all installed modules?
A: The chassis supports up to 5 A at 5 VDC and 1.6 A at 24 VDC across the backplane. Total module loading must remain within these limits.

Q: How does chassis interconnection affect backplane synchronization?
A: When multiple chassis are interconnected, backplane synchronization is extended via interconnect cable, maintaining slot addressing continuity across expanded rack structures.

Field Installation Guidelines

Mount the chassis on a grounded metal panel using designated mounting tabs. Ensure flat surface contact to maintain mechanical rigidity and minimize vibration-induced backplane connector stress. Maintain minimum clearance for airflow across installed modules.

Backplane grounding must be bonded to cabinet PE (protective earth). Avoid routing high-voltage or high-noise conductors parallel to backplane interconnect cables. Use shielded cables where communication modules are installed adjacent to power switching devices.

Module insertion must follow sequential alignment into slot guides to prevent backplane pin deformation. Torque mounting screws uniformly to avoid chassis frame distortion.