Allen-Bradley 1747-L20D SLC 500 Processor Unit

Allen-Bradley 1747-L20D SLC 500 Processor Unit is a fixed-hardware SLC 500 CPU with 20 built-in I/O points, delivering a compact 12-channel 24V DC sink input set and 8-channel 24V DC transistor-source output set for straightforward discrete control. The module requires no separate line-power connection, drawing its operating power from a user-supplied 24V DC source (User Power 24V, up to 200 mA) to power the unit and its I/O circuitry. This configuration makes the 1747-L20D well suited to small automation tasks that already use 24V DC sensors and actuators, such as standalone machines, conveyors, or packaging equipment, enabling direct wiring of sensors to inputs and loads to the transistor outputs. As a member of the SLC 500 family, the 1747-L20D provides a compact, reliable solution for simple, centralized control with 20 I/O points integrated into a single processor unit, ideal for legacy Allen-Bradley control systems that rely on 24V DC logic and actuators.