Allen-Bradley 1785-L40B · PLC-5/40 processor module

The 1785-L40B is the middle-of-the-line PLC-5 processor — 12K user words, 40 I/O racks, the workhorse of American automotive and food-and-beverage lines from 1988 through the early 2000s. Rockwell declared it obsolete in 2017 and stopped repair services in 2020. If your line still runs on PLC-5, you already know why we stock these.

The unit ships with the original keyswitch, battery clip, and remote I/O port cover. We've cycled it on a bench rack for seventy-two hours before shrink-wrapping. Ladder logic transfers cleanly via 1784-KTX card or DH+ over a serviceable AIC.

We keep a small hoard of these for the injection-molding shops and bottling houses that never migrated. When they're gone, they're gone.