Allen-Bradley 1756-A13/B ControlLogix Chassis

Configured for backplane-based module interconnection in ControlLogix I/O chassis systems, the Allen-Bradley 1756-A13/B (1756-A13/B ControlLogix chassis) provides direct physical/electrical execution of module-to-module communication and distributed power routing across 13-slot ControlLogix architectures. The chassis implements horizontal back-panel mounting and establishes a shared deterministic backplane for CPU, I/O, and communication modules within a single integrated rack structure.

Within Allen-Bradley ControlLogix systems, the chassis distributes multi-rail DC power and supports synchronized backplane signaling across all installed modules, enabling coordinated execution of cyclic control and data exchange operations.

Suffix Breakdown & Model Matrix

The suffix “/B” denotes Series revision level of the 1756-A13 chassis platform. “A13” defines a 13-slot ControlLogix backplane chassis configuration. No further factory-defined functional segmentation is assigned.

Hardware Specifications

ControlLogix Backplane Power and Communication Topology

The 1756-A13/B chassis implements a shared backplane architecture where all installed modules interface through a unified electrical and timing bus. The 5.1 VDC and 3.3 VDC rails supply logic-level and ASIC domains, while the 24 VDC rail supports auxiliary module power distribution. Backplane arbitration is handled through deterministic ControlLogix bus scheduling, enabling synchronized data exchange across up to 13 modules without external wiring between slots.

Channel-level communication latency is governed by backplane scan timing, while I/O and processor modules rely on the same internal bus structure for cyclic execution alignment.

Frequently Asked Questions (FAQ)

Q: Does the 1756-A13/B support module hot-swap during operation?
A: Yes. ControlLogix architecture supports hot-swap insertion and removal. However, module-specific state retention depends on individual firmware behavior and configuration.

Q: Is backplane power independently supplied per slot?
A: No. The chassis distributes shared backplane rails. Current limits are defined both per slot and for total chassis load across each voltage domain.

Q: Are communication signals isolated between slots?
A: No. Slot-to-slot isolation is not provided by the chassis. Isolation is implemented at module level where required.

Field Installation Guidelines

• Install chassis in horizontal orientation only as defined by mechanical design constraints

• Ensure proper 8 AWG functional earth and 14 AWG protective earth bonding before energizing system

• Verify backplane connector alignment before module insertion to avoid pin deformation

• Maintain cabinet clearance for airflow due to open-frame chassis design

• Distribute high-power modules across slots to avoid localized backplane rail loading

• Confirm grounding continuity between chassis and cabinet earth bar to reduce noise coupling