Allen Bradley 1747-L553 Ser C 1747-OS501 C FRN 10 SLC 500 5/05 CPU Processor 64K
Surplus Unit Working Used 1747-L553 Ser C 1747-OS501 Ser C FRN 10 1747-L553/C. Allen Bradley SLC 500 1747-05501 1747-0S501 PN-285322 Date Varies. While many Allen Bradley / Rockwell Automation products will have firmware already installed, we makes no representation as to whether a PLC product will or will not have firmware and, if it does have firmware, whether the firmware is the revision level that you need for your application or not.