The Allen-Bradley 1747-M2 is a 4K user‑words EEPROM memory module for the SLC 500 PLC family, used to store the processor's ladder logic and data without requiring a battery for retention. It plugs into the SLC 500 memory interface and provides non‑volatile storage of the program so it remains intact when power is removed. The 1747-M2 is compatible with SLC 5/01 and 5/02 processors, among other SLC 500 configurations, and is listed as a memory option in Rockwell Automation’s documentation.
