Allen-Bradley 1746-A13/B SLC 500 I/O Chassis

Configured for mechanical hosting and backplane electrical distribution in SLC 500 modular controller architectures, the Allen-Bradley 1746-A13/B (1746-A13/B PLC chassis) provides direct physical/electrical execution for module slotting, signal routing, and power rail distribution across SLC 500 I/O subsystems.

The chassis implements a shared backplane structure for 5 VDC and 24 VDC distribution, enabling synchronized module communication across 13 slot positions with deterministic scan alignment under SLC 500 controller control logic.

Hardware Specifications

SLC 500 Backplane Bus Distribution Characteristics

The 1746-A13/B chassis supports SLC 500 backplane bus communication across all installed modules, providing synchronized power and signal distribution through a shared electrical plane. The backplane architecture manages slot addressing, scan sequencing, and module enumeration through fixed electrical indexing.

Multi-module configurations distribute 5 VDC logic power and 24 VDC field power rails across the chassis, requiring compliance with total backplane loading limits to maintain stable module operation under full slot utilization conditions.

Frequently Asked Questions (FAQ)

Q: Can the 1746-A13/B chassis operate with partially populated slots?
A: Yes. Unused slots remain electrically inactive but still part of the backplane structure. Addressing is determined by physical slot position.

Q: What happens if backplane current limits are exceeded?
A: Exceeding 5 VDC or 24 VDC backplane limits can cause voltage drop across the bus, leading to module reset or communication faults.

Q: Is the chassis compatible with mixed module types?
A: Yes. It supports SLC 500 input, output, communication, and specialty modules, provided total backplane power and slot addressing constraints are respected.

Field Installation Guidelines

Mount the chassis on a grounded steel panel using designated mounting points. Ensure flat mechanical contact to avoid chassis torsion that may affect backplane connector alignment across 13 slots.

Maintain separation between backplane interconnect wiring and high-noise conductors. Shielded routing is required for communication modules installed adjacent to switching loads.

Torque all mounting fasteners uniformly to prevent chassis deformation. Verify protective earth continuity between chassis frame and cabinet grounding bar before module installation.