Allen-Bradley 1785-LT PLC-5/15 Processor Module, 1785LT, Control Systems Module

Allen Bradley 1785-LT PLC-5/15 Processor Module: Industrial Control Workhorse

Need rock-solid reliability for your factory floor? The 1785-LT processor module from Allen Bradley’s PLC-5 family keeps production lines humming in manufacturing plants, assembly systems, and material handling operations. This workhorse component manages complex sequences while maintaining millisecond-level response times.

When we installed these modules at a Midwest automotive plant, they kept the robotic welding cells running through 110°F summer temperatures. The 1785-LT plays nice with legacy PLC-5 systems while supporting modern HMIs through its DH+ communication port. Our team regularly pairs them with:

• PLC-5/20 (1785-L20) controllers for mid-sized applications
• 1784-CPUM communication processors for PC integration
• 1771 I/O modules in discrete control setups

What makes this module stand out? Its battle-tested architecture survives where newer systems fail. The non-volatile memory retains programs during power loss, and the modular design lets you swap comms cards without shutting down the whole line. We’ve seen installations maintain 99.98% uptime across 15-year lifecycles.

Key advantages:

• Hot-swappable I/O configuration without system reboot
• Compatible with legacy RSLogix 5 programming software
• Redundant power supply options for critical processes
• Field-replaceable EEPROM cartridges for quick program recovery

For plants stuck between upgrading to ControlLogix and maintaining existing infrastructure, the 1785-LT offers the best of both worlds. Its rugged build handles vibration-heavy environments better than newer surface-mount alternatives, while maintaining enough processing power for most discrete manufacturing tasks.