Migration guides & technical resources

Cross-references and step-by-step plans for replacing obsolete controllers and I/O — written for the engineers doing the work and the buyers sourcing the parts.

SLC 500 migration1747-L551 replacementSLC 500 to CompactLogix1747-AENTR

Allen-Bradley SLC 500 Migration Guide: 1747 Processors & 1746 I/O to CompactLogix

A practical cross-reference for replacing discontinued SLC 500 processors and 1746 I/O with CompactLogix — which controller maps to which CPU, how to keep DH+ and DH-485 devices talking, and how to reuse the existing rack and field wiring with a 1747-AENTR adapter.

Updated 15 Sept 2026Read guide

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