Allen-Bradley SLC 500 Modules: 1746-P4/A Power Supply

Technical Dossier

Product Details And Specifications

Allen-Bradley SLC 500 Series Technical Notes

The Allen-Bradley SLC 500 (Small Logic Controller 500) series, manufactured by Rockwell Automation, is one of the most widely deployed programmable logic controller platforms in global heavy industry. Installed across petrochemical refineries, nuclear auxiliary systems, pulp and paper mills, automotive assembly lines, and water treatment facilities, the SLC 500 platform established a benchmark for modular, rack-based control architecture throughout the 1990s and 2000s. Its fixed and modular chassis configurations — ranging from 4-slot to 13-slot racks — allowed engineers to construct scalable control systems with deterministic scan times and robust I/O density. The 1746-P4/A is a 10A power supply module within this ecosystem, designed to power SLC 500 chassis under high-load configurations.

SLC 500 Full Catalog & Functionalities (SKU List)

Power Supply Modules

• 1746-P1: 5VDC / 2A power supply for 4-slot chassis, standard load applications.
• 1746-P2: 5VDC / 5A power supply for 7-slot and 10-slot chassis, mid-range I/O density.
• 1746-P3: 24VDC input power supply, 5A output; field-powered installations without AC infrastructure.
• 1746-P4: 10A high-capacity power supply for 13-slot chassis with full I/O complement.
• 1746-P4/A: Revised version of 1746-P4 with updated inrush current protection and improved thermal management; primary SKU for this listing.
• 1746-P5: Redundant power supply module for high-availability SLC 500 configurations.
• 1746-P7: 24VDC / 10A power supply, DC-input variant for 13-slot chassis.

CPU / Processor Modules

• 1747-L511: SLC 5/01 processor, 1K memory, DH-485 port, OS501 firmware.
• 1747-L514: SLC 5/01 processor, 4K memory, DH-485 port.
• 1747-L524: SLC 5/02 processor, 4K memory, DH-485 port, higher throughput.
• 1747-L531: SLC 5/03 processor, 8K memory, DH-485 and RS-232 ports.
• 1747-L541: SLC 5/04 processor, 16K memory, DH+ and RS-232 ports.
• 1747-L551: SLC 5/05 processor, 64K memory, Ethernet/IP and DH+ ports; most capable SLC 500 CPU.

Digital Input (DI) Modules

• 1746-IA16: 16-channel 120VAC digital input module, standard industrial AC sensing.
• 1746-IB16: 16-channel 24VDC digital input module, sink/source configurable.
• 1746-IB32: 32-channel 24VDC digital input module, high-density rack applications.

Digital Output (DO) Modules

• 1746-OA16: 16-channel 120/240VAC digital output module, triac output type.
• 1746-OB16: 16-channel 24VDC digital output module, transistor sourcing output.
• 1746-OW16: 16-channel relay output module, dry contact, mixed voltage applications.

Analog I/O (AI/AO) Modules

• 1746-NI4: 4-channel analog input module, 4–20mA / 0–10VDC, 12-bit resolution.
• 1746-NO4I: 4-channel analog output module, current output, 12-bit resolution.
• 1746-NI8: 8-channel analog input module, high-density process variable acquisition.

Communication Adapter Modules

• 1747-SDN: DeviceNet scanner module for SLC 500 chassis, master node configuration.
• 1747-KE: DH-485 to RS-232 interface module for programming and HMI connectivity.