Allen-Bradley 1756-L73 ControlLogix CPU Logix5673 Processor with 8 Mbytes Memory

Product Details

General Information

Memory & Non-Volatile Storage

Communication Ports

Physical & Environmental

Recommended Alternative Models

FAQs

1: What is the difference between the standard 1756-L73 and the 1756-L73S?

A: The standard 1756-L73 is a traditional programmable automation controller (PAC) for standard automation applications. The 1756-L73S is a GuardLogix safety-rated controller that provides 8 MB standard memory plus 4 MB safety memory and supports functional safety up to SIL 3/PLe . They are not interchangeable; safety applications require the -S variant.

2: Does the 1756-L73 support controller redundancy?

A: Yes, the 1756-L73 supports redundant controller configurations within compatible ControlLogix 5570 redundancy architectures. However, this requires a matched second 1756-L73 unit, compatible redundancy modules, a second synchronized chassis, and a properly configured redundancy project in Studio 5000. Both units must run matched firmware — this is not a plug-and-add function.

3: Can I simply swap a 1756-L71 or L72 for a 1756-L73?

A: Direct swap is possible but requires careful verification. When replacing an L71/L72 with an L73, ensure firmware versions match and the project file is properly transferred. However, certain configuration data — such as absolute encoder references and motor database parameters for Kinetix servo axes — may not transfer completely . This can cause position mismatch and homing anomalies. Always verify axis status tags and use the Compare Utility in Studio 5000 to confirm all parameters are correctly migrated.