Overview
The Allen-Bradley 1756-L55 ControlLogix Logix 5555 Processor is a compact processor module for the ControlLogix 1756 modular architecture. Manufactured by Rockwell Automation, this unit delivers reliable control and processing capability in harsh industrial environments. It comes with an integrated 1756-BA1 lithium battery and requires no user-supplied RAM modules, making it a drop-in solution for automation tasks.
Key Features
- Integrated 1756-BA1 Battery: Battery backup included for real-time clock and data retention.
- RS-232 Communication: Built-in serial interface for device programming and diagnostics.
- Low Power Dissipation: Consumes only 5.6–5.7 watts, minimizing thermal load in tight enclosures.
- Industrial-Grade Durability: Tested to IEC 60068 standards for temperature, humidity, vibration, and shock—suitable for demanding factory floors.
- Compact & Lightweight: Weighs 0.35 kg (12.5 oz) for space-constrained applications.
- Studio 5000 Compatible: Programs created in Studio 5000 (formerly RSLogix 5000) run natively on this processor.
Technical Specifications
- Series: ControlLogix 1756
- Processor Type: Logix 5555
- User Memory: None (no application memory included)
- Backplane Current (5.1 V DC): 1.23–1.25 A
- Backplane Current (24 V DC): 0.014 A
- Power Dissipation: 5.6–5.7 W
- Thermal Dissipation: 19.1–19.4 BTU/hr
- Communication Port: RS-232 (serial)
- Isolation Voltage: 30 V continuous
- Operating Temperature: 0 to 60 °C (32 to 140 °F)
- Storage Temperature: −40 to 85 °C (−40 to 185 °F)
- Relative Humidity (noncondensing): 5 to 95%
- Weight: 0.35 kg (12.5 oz)
- Battery Type: 1756-BA1 lithium (replaceable)
- Programming Cables: 1756-CP3 or 1747-CP3
- Certifications: IEC 60068 (EMC, thermal, vibration, shock)
Typical Applications
The 1756-L55 processor excels in:
- Discrete manufacturing (conveyors, packing lines, assembly automation)
- Motion control and servo coordination
- Pump & motor switching applications
- HVAC and facility automation
- Material handling systems
- Equipment retrofits and equipment upgrades where space and power budgets are tight
Compatibility & Replacements
The 1756-L55 mounts directly into any 1756-series ControlLogix backplane (1756-A7, A10, A13, etc.) and communicates via standard Ethernet/IP, ControlNet, or DeviceNet I/O modules. It works seamlessly with Rockwell’s Studio 5000 (RSLogix 5000) engineering environment and accepts the 1756-BA1 backup battery. For systems requiring more user memory, the 1756-L55M13 and higher-series processors (L71, L75) offer expanded RAM. Distributors including DO Supply, PLC Direct, and PLC Hardware maintain stock for immediate shipment.
