Rockwell Automation discontinued the CompactLogix 1769-L32E and 1769-L35E in December 2020. The marketing slide says “move to 5380.” The panel on your floor still says “keep the 1769 I/O.” Those two sentences are not the same project.

Critical rule first: the CompactLogix 5380 platform does not accept 1769 Compact I/O on the local bus. If you must retain existing 1769-XX modules, migrate onto 5370-family L3xER controllers. Jumping straight to 5380 means new 5069 I/O, a Studio 5000 conversion, and usually a panel redesign.

5370 CompactLogix L3 controllers keep the 1769 I/O story alive—the path most plants need when L32E/L35E hardware dies but the rack stays.

Keep the 1769 rack: migrate to 5370

Compatible production-class replacements that still talk 1769 I/O include:

• 1769-L30ER — 1 MB
• 1769-L24ER — ~1.2 MB class (embedded I/O packages vary by catalog)
• 1769-L27ER — ~1.5 MB class
• 1769-L33ER — 2 MB (common L35E landing spot)
• 1769-L36ER — 3 MB (headroom / universal spare)

Memory planning matters more than the brochure. The 1769-L32E carried about 750 KB; 1769-L30ER or larger covers that path. The 1769-L35E sat at about 1.5 MB; 1769-L33ER (2 MB) is the usual direct step, with 1769-L36ER giving expansion room.

Where a plant wants one high-memory 5370 spare on the shelf, the motion-capable 1769-L36ERM is the catalog we stock in that family—useful as a universal field backup when project files for L32E/L35E-class machines are kept offline and ready to download after a controller-type change in Studio 5000.

Migration procedure that actually finishes

1. Export the L32E/L35E project from RSLogix 5000 / Studio 5000 (typically v20/v21-era tooling for these CPUs)
2. Confirm memory headroom on the target L3xER
3. Prefer Series B (or later) L3xER hardware for current firmware support
4. Offline backup before any controller-type change
5. Open the project on the new controller type—Studio prompts the swap—then download
6. Prove 1769 modules online in Controller Tags / I/O tree before releasing the line

Series B L3xER units commonly ship around firmware v20.xx. Bring them to your validated revision with ControlFlash / ControlFlash Plus through RSLinx Classic before you argue about “mystery” I/O states.

1769 I/O that stays on the 5370 path

The 5370 L3xER bus still hosts the classic Compact I/O set plants already own—AC and DC discrete modules such as 1769-IA16 / OA16 / IB16 / OB16E, IQ/OQ families, plus specialty cards like 1769-SM1 and 1769-HSC. That backward compatibility is the entire reason 5370 remains the low-disruption L32E/L35E exit.

Alternate path: CompactLogix 5380 (5069)

If you are ready to leave 1769 behind, 5380 controllers such as 5069-L320ER, 5069-L310ER, and motion-oriented SKUs like 5069-L306ERM (or safety-oriented 5069-L306ER GuardLogix variants where the application demands it) require Compact 5000 I/O—not 1769. Plan on:

• New 5069-L3xER controller
• 5069 I/O such as 5069-IB16 inputs and 5069-OB16 outputs (plus other 5069 catalogs your drawings specify)
• Program conversion in Studio 5000 Logix Designer v28+
• Panel / wiring redesign for the Compact 5000 form factor

For broader Logix rack strategy beyond this migration fork, keep the rest of your spare philosophy aligned with how you already stock PLC and PAC systems.

Field answers

Can 5380 run my existing 1769 modules? No. Keep 5370 if the 1769 rack must stay.

What replaces L35E memory-wise? 1769-L33ER (2 MB) is the usual match; 1769-L36ER (3 MB) adds headroom.

Can one high-memory 5370 back up several L32E/L35E machines? Yes—if the spare’s user memory exceeds each project and you store typed project files for rapid download after a controller change.

Opinion

Most “we were told to go 5380” disasters are I/O disasters. If the panel’s value is in the 1769 modules and field wiring, buy 5370 time. If you are already ripping doors and terminals, then 5380 plus 5069 I/O is the cleaner decade bet. Pick the fork on purpose—not because a discontinuation notice only printed one headline.