The 1756-L74 ControlLogix 5570 Processor Module from Rockwell Automation is a high-memory, high-performance PLC/PAC controller designed for complex industrial automation systems requiring fast deterministic control, large data handling capacity, and strong system scalability.
It is widely used in large manufacturing plants, process industries, and infrastructure automation environments. With 16 MB user memory and full redundancy support, the L74 is positioned as one of the higher-end controllers in the ControlLogix 5570 family, making it ideal for data-intensive and multi-network industrial architectures.
Technical Specifications (Including Size & Weight)
| Parameter | Specification |
|---|---|
| Model | 1756-L74 |
| Series | ControlLogix 5570 |
| Processor Type | PLC / PAC Controller |
| User Memory | 16 MB |
| I/O Memory | ~0.98 MB |
| Nonvolatile Memory | 1 GB SD card (1784-SD1 standard, expandable to 2 GB) |
| Programming Port | USB 2.0 |
| Maximum I/O Capacity | Up to 128,000 digital / 4,000 analog |
| Controller Connections | Up to 500 |
| Controller Tasks | Up to 32 tasks |
| Programs per Task | Up to 100 programs |
| Redundancy Support | Full support |
| Backplane Current (5.1V DC) | ~0.8 A |
| Current Draw (1.2V DC) | ~5 mA |
| Power Dissipation | ~2.5 W |
| Isolation Voltage | 30 V continuous |
| Programming Software | RSLogix 5000 / Studio 5000 |
| Built-in Display | 4-character alpha-numeric display |
| Weight | ~2 kg (shipping weight, typical catalog listing) |
Physical Dimensions
- Size (H × W × D): 133 × 178 × 145 mm
The L74 maintains a standard ControlLogix chassis-compatible design while offering higher memory capacity and expanded redundancy capabilities for large-scale automation systems.
Recommended Related Models
For system expansion or migration planning, the 1756-L74 is commonly paired with:
- 1756-L71 / 1756-L72 / 1756-L73 ControlLogix CPUs
- 1756-EN2T EtherNet/IP communication module
- 1756-ENBT Ethernet bridge module
- 1756-CNB ControlNet bridge module
- 1756-IB16 / 1756-OB16 digital I/O modules
Popular Allen-Bradley ControlLogix Models
Within the same ecosystem, widely deployed controllers include:
- 1756-L61 / L62 legacy mid-range CPUs
- 1756-L63 / L64 high-memory ControlLogix 5560 controllers
- 1756-L71 / L72 / L73 / L74 5570 generation controllers
- 1756-L7SP GuardLogix safety partner modules
- 1756-EN2T high-speed Ethernet modules
These controllers form a scalable automation backbone for both legacy modernization and advanced industrial systems.
