Industrial A21125-B Printed Circuit Board Assembly

A21125-B D21231 is an Allen-Bradley power-supply PCB assembly used in industrial automation equipment and documented for RSLogix 5000-series configurations. It accepts 240 V AC input and delivers up to 10 A of output current, with a verified efficiency of 93%. The module measures 173 mm by 100 mm by 92 mm and weighs 1.5 kg, and it carries an IP20 enclosure rating for basic indoor electrical environments. It provides 2.5 kV input-to-output isolation and operates from -20 °C to +60 °C, supporting reliable performance in demanding conditions. This power-supply board is commonly cataloged together with spare D21231 and appears in equipment listings as a CPU power-supply module for Allen-Bradley systems. Availability can vary; several listings indicate the part has been discontinued by the manufacturer, which can affect warranty terms and aftermarket support. When sourcing this board, confirm exact compatibility with your AB controller model and the associated power interface requirements, and ensure the D21231 spare is included with the A21125-B part in your procurement to guarantee proper electrical interfaces and replacement fit.