Allen-Bradley 1747-L552 SLC 5/05 CPU Module

Allen-Bradley 1747-L552 is an SLC 5/05 CPU module for the SLC 500 family, delivering 32K words of memory and built-in 10BASE-T Ethernet alongside an RS-232 Channel 0 for serial communications. It supports DF1, DH-485, or ASCII on Channel 0, enabling direct connection to programming consoles, HMIs, or other controllers over RS-232, and provides Ethernet networking for PLC-to-SCADA or PLC-to-PLC communications. With a program scan time around 0.9 milliseconds and an I/O scan time near 0.225 milliseconds (depending on I/O load), the L552 fits in up to 30 backplane slots in a compatible SLC chassis, offering a straightforward option for legacy systems needing Ethernet access. This CPU is part of the SLC 5/05 family and thus combines traditional DH+ and RS-232 interfaces with Ethernet connectivity for mixed-network environments; firmware configurations vary by production, and several listings reference FRN 13 for this model.