The Automation Direct P3-550E is a Productivity3000 CPU module for modular PLC systems, offering up to 50 MB of ladder memory and a 4 × 10‑character LCD display for on‑board diagnostics. It provides dual Ethernet 10/100Base‑T ports (RJ45) plus (1) RS‑232 (RJ12) and (1) RS‑485 (3‑pin terminal) serial interfaces and a USB A expansion/host port with USB A storage support. The CPU is designed to mount in the controller slot of a Productivity3000 base and ships with a D2‑BAT‑1 battery to maintain memory; programming is performed with Productivity Suite software (version 2.2 or later). This P3‑550E is listed as discontinued when out of stock, with the P3‑622 as the recommended replacement.
