Allen-Bradley 1747-L553 SLC 5/05 Processor | 64K Memory By wayne No Comments on Allen-Bradley 1747-L553 SLC 5/05 Processor | 64K Memory 3 Min Read Buy the Allen-Bradley 1747-L553 SLC 5/05 CPU with 64K memory, Ethernet, and RS-232. Ideal for medium to large automation systems.