Allen-Bradley 1768-L43S CompactLogix GuardLogix Controller

Configured for safety logic execution and integrated motion control in CompactLogix 1768 platforms, the Allen-Bradley 1768-L43S (1768-L43S GuardLogix Controller) provides direct physical/electrical execution.

Suffix Breakdown & Model Matrix

Hardware Specifications

EtherNet/IP Deterministic Networks and Firmware Flash Compatibility

• EtherNet/IP Deterministic Networks: Coordinates safety I/O data cross-checking over EtherNet/IP and ControlNet deterministic networks using CIP Safety protocol extensions across 1768 communication bridges.
• I/O Density Scaling: Integrates rackless 1769 safety I/O expansion modules and standard I/O banks under a single controller task execution scheme without requiring extra safety partner hardware slots.
• Firmware Flash Compatibility: Maintains cross-revision firmware synchronization via Studio 5000 / RSLogix 5000 environment, enforcing safety signature validation and memory locking routines during firmware flashing.

Frequently Asked Questions

Q: How is memory partitioned within the 1768-L43S GuardLogix controller?

A: The controller contains 2 MB of standard memory for primary logic execution and an independent 0.5 MB safety memory section dedicated to safety task storage.

Q: What are the backplane power supply demands for the 1768-L43S CPU?

A: The processor draws 1.4 A at 24 VDC from the system backplane power supply, resulting in maximum total power consumption of 33.6 W and power dissipation between 4 and 7.5 W.

Q: What precautions must be taken when attaching or removing serial cables during operation?

A: Power must be isolated prior to connecting or disconnecting serial communication cables to prevent hazardous electrical arcing across open contacts in industrial locations.

Field Installation Guidelines

• Chassis Mounting: Mount the controller securely onto a 35 mm DIN rail or chassis panel inside a protective enclosure, verifying top and bottom mounting latches click firmly.
• Grounding Considerations: Ensure the 1768 system mounting rail connects directly to the panel protective earth (PE) ground bus bar to preserve electromagnetic immunity against 10 V/m radiated RF interference.
• Arc Flash Prevention: De-energize backplane and serial port connections before making physical cable modifications to suppress electrical arcing hazards.
• Environmental Limits: Maintain panel cooling air flow to prevent ambient operating temperatures from exceeding 60 deg C under maximum power dissipation