CompactLogix 5370

The Allen-Bradley CompactLogix 5370 (bulletin 1769-L) is a scalable programmable automation controller family from Rockwell Automation, covering standard motion, safety, and panel-free "Armor" variants within a single platform. The catalog number encodes key attributes: the numeric suffix indicates memory tier (e.g., L37 = 3–4 MB, L38 = 5 MB, L43 = 2 MB, L45 = 3 MB), ERM denotes dual EtherNet/IP ports with motion capability, O designates the Armor (panel-free, IP67-rated) variant, S identifies Compact GuardLogix safety controllers carrying a separate safety memory partition, and a trailing K indicates conformal coating for harsh environments. Representative models include the 1769-L45 (3 MB standard controller), the 1769-L38ERM (5 MB, 31 local 1769 I/O, dual EtherNet/IP motion), the 1769-L38ERMS (5 MB standard / 1.5 MB safety, GuardLogix), and the 1769-L38ERMO (Armor, 5 MB, 80 nodes). All controllers in this family communicate over EtherNet/IP, an open industrial Ethernet protocol. With 60 catalog numbers available, PLC Exchange maintains broad in-stock coverage across memory, safety, motion, and environmental configurations.