ABB DSSR120 PoWer Supply Unit

Product Overview

The DSSR120 is a heavy-duty, high-current DC-DC power supply unit engineered for the demanding power requirements of ABB’s industrial control platforms. This module is designed to step down a standard 24V industrial DC bus (accepting an input range of 18-30V DC) into a precision-regulated 5V DC output. Capable of delivering up to 20 Amps, the DSSR120 is a critical component for powering logic-level electronics, backplane buses, and high-density processor modules within PLC and DCS racks. Its robust internal architecture is built for continuous 24/7 operation, featuring high-grade thermal management to maintain stability under full-load conditions.

Technical Specifications

• Model Number: DSSR120

• Converter Type: Regulated Step-Down DC-DC Power Supply

• Input Voltage Range: 18V to 30V DC (Nominal 24V DC)

• Maximum Input Power: 140 W

• Regulated Output Voltage: 5V DC

• Maximum Output Current: 20 A

• Operational Load Range: 1 A to 20 A

• Physical Weight: 4.54 lbs (2.06 kg)

• Mounting Compatibility: Standard ABB industrial subrack or control panel integration

• Cooling Requirement: Passive convection or forced-air depending on cabinet density

• Internal Protection: Integrated overcurrent and overvoltage suppression

Lifecycle Reliability and Maintenance

The DSSR120 is frequently utilized as a core component in preventive maintenance kits for large-scale automation systems. Because 5V rails are the lifeline for digital logic, this module includes high-endurance capacitors and rapid-response fuses to safeguard against input transients. In many legacy DCS installations, replacing the DSSR120 is a standard procedure during 5-to-10-year overhauls to ensure that the aging electrolytic components do not compromise the integrity of the system's central processing logic.