Allen-Bradley 1745 Series Modules – AB 1745-E102 Expansion Unit

Technical Dossier

Product Details And Specifications

Allen-Bradley 1745 Series Technical Notes

The Allen-Bradley 1745 series, developed by Rockwell Automation, represents the SLC 100 and SLC 150 programmable controller platform — one of the earliest modular PLC architectures deployed at industrial scale. Installed across chemical processing plants, petroleum refineries, nuclear auxiliary systems, and continuous manufacturing lines throughout the 1980s and 1990s, the 1745 platform established the foundational I/O expansion and processor architecture that later evolved into the SLC 500 (1746/1747) family. Despite its end-of-life status, the 1745 series remains embedded in legacy control infrastructure worldwide, requiring ongoing spare parts support for facilities operating on extended maintenance cycles.

The Evolution of 1745 Architecture

Q: How are RFQ terms confirmed?
A: Quantity, required condition, documentation needs, destination and sourcing route are confirmed during RFQ review before quotation.

The transition from 1745 to the SLC 500 (1746/1747) series in the early 1990s introduced a fully modular backplane, standardized I/O addressing, and broader network compatibility. Plants that did not migrate remain dependent on 1745 hardware, as the programming environment (APS software on DOS) and I/O addressing are not forward-compatible with RSLogix 500 or Studio 5000. Cross-referencing to modern equivalents requires full system re-engineering rather than a drop-in replacement.

1745 Full Catalog & Functionalities (SKU List)

Expansion Units (I/O Chassis)

• 1745-E101: 4-slot expansion chassis for SLC 150, single-rail backplane, 24 VDC bus
• 1745-E102: 8-slot expansion unit for SLC 150, extended I/O capacity, DIN-rail or panel mount
• 1745-E103: 4-slot expansion chassis, alternate power configuration for SLC 150 systems
• 1745-E105: 5-slot expansion unit, compact form factor for space-constrained enclosures
• 1745-E151: SLC 150 expansion chassis, 4-slot, 120 VAC power supply integrated
• 1745-E152: 8-slot expansion chassis, 120 VAC, high-density I/O configuration
• 1745-E153: 4-slot expansion chassis, 240 VAC power supply variant
• 1745-E155: 5-slot expansion chassis, 240 VAC, for European and industrial 240 V installations

Processors (SLC 100 / SLC 150)

• 1745-LP101: SLC 100 processor, 256-word data table, 500-instruction program memory, RS-232 port
• 1745-LP151: SLC 150 processor, 640-word data table, DH-485 network port, 1K program memory
• 1745-LP152: SLC 150 processor, enhanced memory, 2K ladder program capacity
• 1745-LP153: SLC 150 processor with expanded I/O addressing, supports up to 3 expansion chassis
• 1745-LP154: SLC 150 processor, 4K program memory, extended data file support
• 1745-LP155: SLC 150 processor, high-capacity variant, 8K program memory
• 1745-LP156: SLC 150 processor, maximum configuration, supports full 1745-E1xx expansion range

Programming & Interface Devices

• 1745-PT1: Hand-held programmer terminal for SLC 100/150, keypad entry, 2-line LCD display
• 1745-PT2: Advanced hand-held programmer, extended function key set, offline program storage
• 1745-PRGM: PC-based programming interface cable and adapter kit for APS software connectivity

Quality Control for the 1745 Range

The 1745 series uses a proprietary backplane bus architecture that requires point-to-point electrical verification rather than standard protocol-layer testing. DriveKNMS applies the following test procedures to all 1745 modules prior to shipment:

• Backplane bus continuity and impedance check across all I/O slot connectors
• Processor power-on self-test (POST) verification with APS programming terminal
• DH-485 and RS-232 port communication integrity test at rated baud rates
• I/O module channel-level functional test: discrete input/output state verification under load
• Visual inspection for capacitor degradation, PCB corrosion, and connector pin condition
• Burn-in cycle: 48-hour powered operation under ambient temperature monitoring