ABB / Baldor / Reliance PSM125ES AutoMax DC Bus Supply Module

The PSM125ES AutoMax DC Bus Supply Module is a three-phase AC-to-DC rectifier designed to supply stable DC bus voltage to SA500 Power Modules within the AutoMax Distributed Power System. The module rectifies three-phase 230 VAC input power and delivers a nominal 325 VDC output to support distributed motor control architectures. Up to six Power Modules can be daisy-chained from a single supply, with remote Power Module placement possible up to 750 meters (2500 feet) from the AutoMax rack.

Technical Specifications

• Input Power: Three-phase 230 VAC


• DC Bus Output: 325 VDC nominal


• Power Module Daisy-Chain Capacity: Up to six modules


• Maximum Remote Distance: 750 meters (2500 feet) from AutoMax rack


• Rectification Architecture: Three-phase bridge of SCRs and diodes with phase-angle fired SCR control for DC bus capacitor charging current regulation


• Braking Management: Integrated braking circuit using bi-polar transistor switch and resistor for motor regeneration handling


• Control & Regulation: Digital execution via Universal Drive Controller (UDC) module and Power Module Interface (PMI)


• Communication Link: Fiber-optic connection between UDC and PMI


• Software Configuration: AutoMax Programming Executive version 3.4 or later

Key Features

• SCR firing phase angle adjustment during capacitor charging for controlled current inramp


• Distributed power architecture supporting extended cable runs


• Fiber-optic isolation for noise immunity in industrial environments


• Integrated regenerative braking for motor deceleration management

Typical Applications

• Multi-motor industrial automation systems requiring distributed DC bus architecture


• Induction motor and permanent magnet brushless motor drive systems


• Factory floor installations where Power Modules must be remotely located from central control

Compatibility & Integration The PSM125ES integrates within the AutoMax Distributed Power System framework and supplies DC bus voltage exclusively to SA500 Power Modules. Distributed system design allows Power Module placement throughout facility layouts without proximity constraints to the main AutoMax rack.