Allen Bradley 1746-A7 SLC 500 7-Slot Chassis with Processor and Power Supply

The Allen Bradley 1746-A7 is a 7-slot chassis from the SLC 500 family of modular programmable logic controllers, built for compact control systems requiring the right balance of capacity and panel space. This chassis houses the modular processor, communication adapter modules, and input/output modules, providing the mechanical and electrical backbone for SLC 500 automation systems. The 1746-A7 can be used as a standalone unit or can work with one or two additional local chassis using chassis interconnection cables to create a total of 30 I/O slots.

Technical Specifications

The 1746-A7 chassis provides 7 slots for SLC 500 series modules including the processor, power supply, and I/O modules. The backplane current rating is 10 A at 5 V DC, ensuring sufficient power distribution for populated module configurations. The chassis measures 28.2 x 17.1 x 14.5 cm (11.3 x 6.8 x 5.8 inches) and weighs approximately 1.1 kg (2.4 lbs). Mounting is via panel mount with four mounting tabs. The operating temperature range is 0 to 60 degrees Celsius, with storage temperature from -40 to 85 degrees Celsius. Thermal dissipation is 2.5 BTU per hour at 28.8 V DC.

System Expansion Capabilities

The SLC 500 chassis can be expanded using chassis interconnection cables including the 1746-C9 and 1746-C7 cables. The system supports up to two expansion chassis, enabling configurations with up to 30 I/O slots maximum. Interconnect chassis vertically with the 1746-C9 cable or 1746-C16 cable in different lengths. Each chassis in a multi-chassis configuration requires its own power supply, such as the 1746-P2. This modular architecture allows engineers to scale system I/O capacity according to application requirements while maintaining a compact footprint for smaller installations.

System Components

The 1746-A7 chassis houses the 1747-L571W SLC 5/04 processor module, a high-performance CPU with DH+ communication capability for peer-to-peer networking and programming connectivity. The chassis also accommodates the 1746-P2 power supply module, which provides the necessary DC power to the backplane for all installed modules. Bulletin 1746 SLC I/O provides a full range of digital, analog, and specialty I/O modules for a wide variety of applications. These I/O modules can be used in a local I/O chassis of an SLC 500 controller or in expansion chassis configurations.

Applications

The Allen Bradley 1746-A7 with 1747-L571W processor and 1746-P2 power supply is deployed in industrial automation applications requiring SLC 500 platform control with moderate I/O capacity. Typical applications include machine control in manufacturing facilities, conveyor system automation in distribution centers, packaging machinery control, and material handling systems. The SLC 500 platform is also used in water treatment plants, building automation systems, and any industrial application where the proven reliability of the SLC 500 architecture is required for discrete and process control applications with up to 30 I/O slots of expansion capacity.