Overview
The Allen-Bradley 1747-PIC /A is an RS-232 to DH-485 interface converter engineered for SLC 500 series legacy control systems. This accessory bridges serial communication protocols, allowing PCs and serial terminals to communicate with Allen-Bradley SLC 5/01, 5/02, and 5/03 processors over DH-485 networks. Discontinued by Rockwell Automation as of December 31, 2015, the 1747-PIC /A remains critical infrastructure in many industrial environments running mature SLC 500 platforms.
Key Features
- Protocol Conversion — Converts RS-232 signals to DH-485, enabling seamless integration between serial devices and DH-485 networks
- SLC 500 Compatibility — Directly interfaces SLC 5/01, 5/02, and 5/03 processors for diagnostics and programming access
- 25-Pin D-Sub Connector — Standard DB25 connector on PC side; includes dedicated cable for DH-485 network connection
- Native COM Port Support — Works with built-in COM1 and COM2 serial ports; native compatibility with RSLogix 500 and RSLinx software
- Compact Industrial Design — Rugged construction for harsh environments; includes 279.4 mm ribbon cable for computer serial port connection
Technical Specifications
- Device Type — RS-232 to RS-485 (DH-485) Interface Converter
- Processor Compatibility — SLC 5/01, SLC 5/02, SLC 5/03
- Primary Interface — RS-232 serial, 25-pin D-sub connector (DB25)
- Network Interface — DH-485 network via 1747-C10 cable (separate)
- Dimensions — 13 cm (L) × 10 cm (W) × 20 cm (H)
- Weight — 0.29 kg (0.55 lbs)
- Operating Systems — Windows 2000, Windows XP and later (with RSLinx/RSLogix 500)
- Manufacturer Status — Discontinued (End-of-Life: 12/31/2015)
- Cable Included — 279.4 mm (11 in.) ribbon cable for serial port connection
Typical Applications
- Legacy System Programming — Upload/download logic to SLC 5/03 fixed and modular controllers via RSLogix 500
- System Diagnostics — Monitor processor status, forces, and real-time data from older SLC platforms
- Maintenance and Troubleshooting — Enable field technicians to access and modify control code on established production systems
- Mixed Network Integration — Bridge serial devices and operator terminals to DH-485-based plant floors without full system replacement
Compatibility & Replacements
The 1747-PIC /A is the revision A variant of the original 1747-PIC. It is compatible with SLC 500 20-point fixed controllers, modular controllers with DH-485 expansion chassis, and all SLC 5/01–5/03 series processors. Note: The converter works only with native COM1 and COM2 ports and is not compatible with USB-to-serial adapters or serial port extender boards. For newer Allen-Bradley networks (ControlLogix, CompactLogix, or EtherNet/IP-based systems), this device will not operate; modern systems require Ethernet-based communication modules. The 1747-C10 DH-485 network cable and optional 9-pin to 25-pin adapter are sold separately.
