+15V 20A P.S. H725

This document is a technical schematic for a +15V 20A power supply unit (model H725) designed by Digital Equipment Corporation.

Key components and features include:

• Transformer and Rectification: The schematic details the input transformer wiring configuration, which allows for various nominal input voltages ranging from 100V to 240V at both 50Hz and 60Hz. It utilizes a bridge rectifier circuit (diodes D1 and D2) to convert the AC input to DC.
• Output: The power supply provides a +15V DC output through two connectors (J1 and J2), each with designated pins for the positive voltage and the return path.
• Filtering: The circuit includes a capacitor bank (C1, C2, C3, C4) totaling 57,000 µF to smooth the rectified DC output, alongside resistors (R1, R2) for load regulation.
• Configuration Table: A conversion table is provided, specifying the necessary jumper settings for different input voltage and frequency requirements.
• Parts List: The document includes a summary table of the components used, including the transformer, cooling fan, diodes, and capacitor specifications.