The Allen-Bradley 1745-E105 SLC 100 Expansion Unit is an expansion module for the SLC-100 and SLC-150 PLC families that adds I/O capacity to an existing controller. When paired with a compatible SLC processor, it extends the number of I/O circuits to a maximum of 112, enabling larger or more complex control schemes without replacing the main CPU. This expansion unit is commonly used to retrofit legacy automation setups or incrementally scale a system by adding additional I/O points to support more sensors, actuators, and I/O devices in manufacturing and process environments.
