Allen Bradley 1747-L552 Ser B 1747-OS501 C FRN SLC 500 5/05 CPU Processor 32K
Surplus Unit Working Used 1747-L552 Ser B 1747-OS501 Ser C FRN Varies 1747-L552/C. Allen Bradley SLC 500 1747-OSSOI 1747-05501 1747-0S501 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.