Overview
The Allen-Bradley 1747-L541 is a high-performance SLC 5/04 processor from the proven SLC 500 modular controller line. This CPU module integrates 16K words of user memory with dual communication interfaces (DH+ and RS-232), making it suitable for medium to large distributed I/O applications in manufacturing, HVAC control, material handling, and SCADA systems. The unit features battery-backed CMOS RAM and a 3-position front-panel keyswitch for mode selection.
Key Features
- 16K words of user memory with battery backup protection
- Dual communication channels: Data Highway Plus (DH+) and RS-232 serial port
- Supports up to 4,096 digital input and 4,096 output points
- Handles up to 480 analog I/O points via compatible modules
- Fast program scan time of 0.9 ms/K with 0.225 ms I/O scan time
- Multiple LED status indicators (RUN, FLT, BATT, FORCE, DH+, RS-232) for diagnostics
- User-selectable Run, Remote, or Program modes via front keyswitch
- Supports remote I/O, DeviceNet pass-through, and indirect addressing
Technical Specifications
- Processor Type: SLC 5/04 CPU Module
- Memory (User): 16K words
- Memory (Backup Flash): 64K words (1747-M13 device)
- Digital I/O Capacity: 4,096 inputs + 4,096 outputs (maximum)
- Analog I/O Capacity: 480 points (via compatible modules)
- Program Scan Time: 0.9 milliseconds per K word
- I/O Scan Time: 0.225 milliseconds typical
- Power Supply Requirements: 1 Amp at 5V DC; 200 mA at 24V DC (backplane)
- Interrupts (STI/DII): 1 millisecond selectable timed; 0.5 milliseconds discrete input
- Communication Interfaces: DH+ (57.6 Kbaud) and RS-232 (9-pin, 19.2 Kbaud default)
- Operating Temperature Range: 0°C to 60°C (32°F to 140°F)
- Mounting: SLC 500 modular chassis with backplane connection
- Series: Series B, Series C available
Typical Applications
The 1747-L541 is ideal for:
- HVAC and building automation systems
- SCADA and supervisory control networks
- Material handling and conveyor control
- Manufacturing and assembly line process control
- Distributed I/O applications using Remote I/O modules
- Food processing, water treatment, and chemical plant automation
- Systems requiring multi-drop DF1 or DH-485 peer-to-peer communications
Compatibility & Replacements
Compatible With
- SLC 500 modular chassis (all sizes: 4-slot, 7-slot, 10-slot, 13-slot)
- SLC 500 I/O modules (input, output, analog modules)
- SLC 500 communication adapters (DeviceNet, Remote I/O scanners)
- 1747-M13 flash memory modules for backup storage (Series C OS401+)
- Messaging with SLC 500, PLC-2, PLC-5, and ControlLogix processors via DH+
- Rockwell Automation RSLogix 500 programming software
- ASCII printers and bar-code readers via RS-232 port
- Third-party Modbus RTU slave devices via RS-232
Replaces / Drop-In Replacement For
- Earlier SLC 5/03 systems (with software recompilation)
- Legacy 1747-L541 Series A units (backward compatible)
- Verify compatibility with your original configuration before replacement
Works With
- RSLogix 500 programming environment
- Data Highway Plus (DH+) industrial network protocol
- DF1 and DH-485 peer-to-peer serial protocols
- Modbus RTU master/slave communication
- ASCII I/O for serial device integration
- Remote I/O distributed control architecture
- Allen-Bradley and Rockwell Automation third-party integrations
