Allen-Bradley 1768-L43/B CompactLogix Processor

The Allen-Bradley 1768-L43/B, also cataloged as the 1768-L43 CompactLogix Processor, operates as a dedicated hardware component for central logic execution and system orchestration within CompactLogix control platforms.

Suffix Breakdown & Model Matrix

Hardware Specifications

Backplane Bus Communication Velocity and I/O Density Scaling

• Backplane Bus Communication Velocity: Processes up to 250 concurrent CIP logical connections directly across the internal 1768 backplane rail, transmitting high-density scheduled control data without scan overhead.
• I/O Density Scaling: Direct backplane integration manages up to 2 local high-speed 1768 communication interface modules alongside a maximum of 16 local and remote 1769 I/O modules distributed across 2 I/O banks.
• Firmware Flash Compatibility: Fully compatible with Studio 5000 / RSLogix 5000 software for execution configuration, online routine editing, and firmware flashing via connected communication bridges.

Frequently Asked Questions

Q: What is the maximum number of local 1768 communication modules supported by the 1768-L43/B processor?

A: The processor features 2 dedicated local 1768 slots, supporting up to 2 local 1768 communication modules (such as the 1768-ENBT or 1768-CNB).

Q: What are the backplane current draw and total power consumption metrics for this Series B unit?

A: The controller draws 1.3 A at 24 VDC from the backplane, consuming 31.3 W of operational power with a thermal dissipation rating of 6.3 W.

Q: What is the maximum total connection capacity for standard and remote network devices?

A: The unit manages up to 250 total simultaneous CIP logical connections across its backplane and communication ports.

Field Installation Guidelines

• Chassis Mounting: Secure the processor assembly to the panel using #8 or M4 mounting screws torqued to 1.16 Nm to ensure mechanical stability against operational shock and vibration.
• Wiring Standards: Route all communication port cables according to Category 2 industrial wiring standards to minimize noise coupling and preserve signal integrity.
• System Grounding: Confirm the 1768 DIN rail or backplate is bonded directly to the main cabinet protective earth (PE) grounding bar with low-impedance copper conductors.
• Expansion Bank Control: Limit local 1769 Compact I/O module layouts to a maximum of 2 I/O banks, ensuring expansion bus cables and bank end caps are fully locked before applying system power.