Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 1746-A7 |
| Manufacturer | Allen-Bradley (Rockwell Automation) |
| Product Type | SLC 500 Modular Chassis / Backplane |
| Number of Slots | 7 |
| Compatible Series | SLC 500 Series |
| Backplane Communication | Proprietary Parallel SLC 500 Backplane |
| Power Distribution | Distributes +5 VDC logic power from power supply to all slots |
| Chassis Power Requirements | Powered by an external 1746-P1, P2, P3, P4, P5, or P7 power supply |
| Module Compatibility | All SLC 500 series processors and I/O modules (1746-XXXX) |
| Isolation | 500V AC isolation between backplane and chassis ground |
| Mounting | Panel mount (keyhole slots) or DIN rail mount (with optional 1746-N2 kit) |
| Operating Temperature | 0°C to 60°C (32°F to 140°F) |
| Storage Temperature | -40°C to 85°C (-40°F to 185°F) |
| Relative Humidity | 5% to 95% non-condensing |
| Agency Certifications | c-UL-us, CE, C-Tick |
| Dimensions (H x W x D) | Approx. 305 mm x 220 mm x 110 mm (12.0″ x 8.66″ x 4.33″) |
| Weight | Approx. 2.0 kg (4.4 lb) |
| Material | Steel chassis with polycarbonate card guides |
Main Features and Advantages
Robust and Flexible System Foundation: The primary advantage of the Allen-Bradley 1746-A7 is its role as a versatile and scalable platform. The seven slots allow for a tailored system configuration that can grow with application needs. Users can install a processor, various combinations of high-density digital I/O (like the 1746-IB32 or OB32), analog modules, and communication adapters (like the 1747-KFC or 1747-SN) in any order, though the processor typically occupies slot 0. This modularity prevents paying for unused capacity and allows for precise system design. The robust steel construction and secure card guides ensure modules are firmly held and protected from vibration, a critical factor in industrial environments. The chassis is designed for easy serviceability; modules can be individually inserted or removed with a locking screw mechanism without disassembling the entire unit.Simplified Integration and Proven Reliability: The 1746-A7 chassis simplifies system integration by providing a unified backplane. This eliminates the need for complex inter-module cabling, as all communication occurs via the internal bus, reducing wiring errors and improving system reliability. The chassis is designed to work seamlessly with the wide ecosystem of SLC 500 power supplies and modules, ensuring interoperability. Its design supports hot swapping of I/O modules (with proper procedures) in certain configurations, which can reduce downtime during maintenance. The Allen-Bradley 1746-A7 is the cornerstone of a proven, battle-tested control platform. Its widespread use over decades means extensive documentation, readily available spare parts, and a deep pool of technical knowledge, making it a low-risk, dependable choice for both new installations and legacy system support. Its balance of slot capacity, physical size, and cost-effectiveness has made it one of the most popular chassis in the SLC 500 family.
