Allen-Bradley SLC 500 1746 Modules – 1746-A13

Technical Dossier

Product Details And Specifications

Allen-Bradley SLC 500 1746 Series Technical Notes

The Allen-Bradley SLC 500 platform, built on the 1746 backplane architecture, is one of the most widely deployed small-to-mid-range programmable logic controller families in global heavy industry. Installed across petrochemical complexes, nuclear auxiliary systems, oil refinery process units, pulp and paper mills, and automotive assembly lines, the SLC 500 series established a benchmark for modular I/O density and deterministic ladder-logic execution in the 1990s and 2000s. Its chassis-based slot architecture — ranging from 4 to 13 I/O slots — allows engineers to configure discrete, analog, specialty, and communication modules within a single backplane, reducing panel footprint and simplifying field wiring. The 1746-A13, a 13-slot chassis, represents the maximum expansion capacity within the standard SLC 500 fixed-backplane lineup and remains a critical spare part for facilities operating legacy SLC 5/03, 5/04, and 5/05 processors.

The Evolution of SLC 500 / 1746 Architecture

The SLC 500 family was introduced by Allen-Bradley (now Rockwell Automation) in the late 1980s as a successor to the SLC 100 and SLC 150 fixed controllers. The 1746 backplane standard defined a parallel I/O bus that allowed processors and I/O modules to communicate at deterministic scan rates. Early processors — the SLC 5/01 and 5/02 — used DH-485 as the primary network interface. The SLC 5/03 added RS-232 and DH-485 simultaneously. The SLC 5/04 introduced Data Highway Plus (DH+) for peer-to-peer communication across larger plant networks. The SLC 5/05 added native Ethernet/IP, bridging the SLC platform into modern TCP/IP plant architectures.

SLC 500 / 1746 Full Catalog & Functionalities (SKU List)

Chassis & Power Supplies

• 1746-A13: 13-slot SLC 500 modular chassis, standard backplane, accepts all 1746 I/O modules
• 1746-A10: 10-slot SLC 500 modular chassis, standard backplane
• 1746-A7: 7-slot SLC 500 modular chassis, compact panel installations
• 1746-A4: 4-slot SLC 500 modular chassis, minimum-slot configuration
• 1746-P1: 120/240 VAC power supply, 2A @ 5VDC, for 4- and 7-slot chassis
• 1746-P2: 120/240 VAC power supply, 4A @ 5VDC, for 10- and 13-slot chassis
• 1746-P3: 24 VDC input power supply, 2A @ 5VDC, for 4- and 7-slot chassis
• 1746-P4: 120/240 VAC power supply, 10A @ 5VDC, high-load chassis configurations

CPU / Processor Modules

• 1747-L511: SLC 5/01 processor, 1K memory, DH-485 port
• 1747-L514: SLC 5/01 processor, 4K memory, DH-485 port
• 1747-L524: SLC 5/02 processor, 4K memory, DH-485 port
• 1747-L531: SLC 5/03 processor, 8K memory, DH-485 + RS-232 ports
• 1747-L541: SLC 5/04 processor, 16K memory, DH+ + DH-485 + RS-232 ports
• 1747-L551: SLC 5/05 processor, 64K memory, Ethernet/IP + DH-485 + RS-232 ports

Digital Input (DI) Modules

• 1746-IB16: 16-point 24 VDC sink digital input module
• 1746-IB32: 32-point 24 VDC sink digital input module, high-density
• 1746-IA16: 16-point 120 VAC digital input module
• 1746-IM16: 16-point 220 VAC digital input module

Digital Output (DO) Modules

• 1746-OB16: 16-point 24 VDC source digital output module
• 1746-OB32: 32-point 24 VDC source digital output module, high-density
• 1746-OA16: 16-point 120/240 VAC triac output module
• 1746-OW16: 16-point relay output module, 120/240 VAC or 24 VDC

Analog Input/Output (AI/AO) Modules

• 1746-NI4: 4-channel analog input, 4–20 mA / 0–10 VDC selectable
• 1746-NI8: 8-channel analog input, 4–20 mA / 0–10 VDC selectable
• 1746-NO4I: 4-channel analog current output, 4–20 mA
• 1746-NO4V: 4-channel analog voltage output, 0–10 VDC

Communication & Specialty Modules

• 1747-SDN: DeviceNet scanner module for SLC 500 chassis
• 1747-SN: Remote I/O scanner module, DH+ network
• 1746-BAS: BASIC module for custom ladder-logic extensions

Quality Control for the SLC 500 / 1746 Range

All 1746-series chassis and modules processed by DriveKNMS undergo a structured test protocol prior to shipment. Chassis units — including the 1746-A13 — are inspected for backplane bus integrity, slot connector pin condition, and power rail continuity. Processor modules are bench-tested under live ladder-logic execution with DH-485 and Ethernet/IP communication verification where applicable. Analog I/O modules are calibrated against NIST-traceable reference instruments to verify channel accuracy within published specifications. Digital I/O modules are cycled through full point-by-point functional tests. All units are cleaned, re-labeled with test date and technician ID, and packed in anti-static packaging with desiccant.