1756-A4 ControlLogix 4-Slot Chassis | Allen-Bradley

The Original New Allen-Bradley 1756-A4 ControlLogix 4-Slot Chassis is the foundational backplane for building compact ControlLogix automation systems. It provides the physical mounting and high-speed communication backbone for up to four ControlLogix controllers, I/O modules, communication adapters, and specialty modules. The chassis backplane distributes power to each installed module and enables seamless data exchange between all system components. Designed for horizontal back-panel mounting in industrial control cabinets, the 1756-A4 is ideal for space-constrained applications requiring a small footprint with robust ControlLogix performance.

Core Engineering Highlights:
4 module slots | High-speed ControlBus backplane | Horizontal back-panel mounting only | 15A @ 5.1V DC / 2.8A @ 24V DC backplane current | 4W max power dissipation | 0°C to 60°C operating temperature | 0.75 kg (1.7 lb) weight

Key Features:

• Original New Allen-Bradley 1756-A4 chassis

• 4 slots for ControlLogix 1756 series modules

• High-speed ControlBus backplane for rapid data exchange between modules

• Horizontal back-panel mounting only (not DIN rail compatible)

• Modular design allows mixing controllers, I/O, communication, and specialty modules

• Hot-swappable module replacement without powering down the entire system

• Electronic keying prevents incorrect module installation

• Open-style enclosure with convection cooling

• Rugged construction for demanding industrial environments

• UL Listed, CE marked, ATEX and IECEx certified

Applications:

• Central backplane for ControlLogix and GuardLogix control systems

• Compact machine control and manufacturing automation

• Small-scale process control and OEM equipment

• Material handling and conveyor systems

• Legacy system upgrades and retrofit projects

• Space-constrained control panels and cabinets

Technical Specifications:

General

• Catalog Number: 1756-A4

• Product Type: ControlLogix Chassis

• Number of Slots: 4

• Series: Series B (Standard)

• Mounting: Horizontal back-panel mounting only

• Enclosure Type: Open-style (IP20 equivalent)

Backplane Current Ratings

• Power Dissipation (Max): 4W

• Minimum Cabinet Size (HxWxD): 50.8 x 50.8 x 20.3 cm (20 x 20 x 8 in.)

• Dimensions (HxWxD): 169 x 263 x 145 mm (6.65 x 10.35 x 5.71 in.)

• Weight: Approx. 0.75 kg (1.7 lb)

Environmental

• Operating Temperature: 0°C to 60°C (32°F to 140°F)

• Storage Temperature: –40°C to 85°C

• Relative Humidity: 5% to 95% non-condensing

• Vibration: 2 g @ 10–500 Hz

• Shock (Operating): 30 g

• Shock (Non-operating): 50 g

Wire Sizes

• Functional Earth Ground: 8.3 mm² (8 AWG) solid or stranded copper wire, rated 90°C or greater

• Protective Earth Ground: 2.1 mm² (14 AWG) solid or stranded copper wire, rated 90°C or greater

System Compatibility:

• Rockwell Automation ControlLogix 1756 controllers (all series)

• GuardLogix safety controllers

• 1756 I/O modules (digital, analog, specialty, diagnostic, motion control)

• 1756 communication modules (EtherNet/IP, ControlNet, DeviceNet)

• 1756 power supplies (1756-PA72, 1756-PA75, 1756-PB72, etc.)

• 1756 redundancy modules (advanced redundancy requires specific chassis compatibility)

• Any 1756 module that works in one ControlLogix chassis works in all chassis sizes

Related Products:

• 1756-A4K – Conformally coated version for harsh environments

• 1756-A7 – 7-slot chassis for larger systems

• 1756-A10 – 10-slot chassis

• 1756-A13 – 13-slot chassis

• 1756-A17 – 17-slot chassis

• 1756-PA72 / 1756-PA75 – ControlLogix AC power supplies

• 1756-PB72 – ControlLogix DC power supply

• 1756-L7x / 1756-L8x – ControlLogix controllers

• 1756-EN2T / 1756-EN2TR – EtherNet/IP communication modules

• 1756-IB32 / 1756-OB32 – Digital I/O modules

• 1756-RM / 1756-RM2 – Redundancy modules for mission-critical applications

• 1756-BA1 / 1756-BA2 – Lithium battery backup for controller memory

PLC ERA is an independent industrial automation distributor supplying 100% genuine Original New products through established global supply channels. Allen-Bradley, ControlLogix, and GuardLogix are trademarks of Rockwell Automation.