MEAN WELL RT-125B 125W Triple Output Switching Power Supply 5V/12V/-12V Chassis Mount

In industrial control panels and automation systems, the MEAN WELL RT-125B delivers reliable triple-output DC power from a universal AC input. It provides +5 V at up to 15 A, +12 V at up to 5 A, and -12 V at up to 1 A, with a total output power of 125 W. The chassis-mount design and free air convection cooling make it easy to integrate into equipment without additional fans. This power supply is ideal for powering logic circuits, motors, and interface boards in factory machinery, test instruments, and communication devices.

Key specifications

• Total output power: 125 W
• Outputs: +5 V / 15 A, +12 V / 5 A, -12 V / 1 A
• Input voltage: 88–264 VAC or 125–373 VDC
• Efficiency: 78% typical
• Protections: overload, over voltage, short circuit
• Cooling: free air convection
• Operating temperature: -20 to +70 °C
• Safety standards: UL 60950-1, TUV EN 60950-1, CB, CE
• Ripple & noise: 80 mVp-p (+5 V), 120 mVp-p (±12 V)
• Mounting: chassis mount
• Voltage adjustment range (CH1): ±10%
• Isolation voltage: 3 kVAC (input to output)

Why choose it

The RT-125B combines three regulated outputs in a compact, open-frame chassis. Its wide input voltage range accepts both AC and DC sources, making it versatile for global use. Built-in protections and compliance with international safety standards ensure long-term reliability in demanding environments.

Ideal use cases

• Industrial automation and control systems
• Test and measurement equipment
• Telecommunication devices
• Embedded systems requiring multiple DC rails

Good to know

The +5 V output can be adjusted by ±10% to compensate for voltage drops in wiring. The power supply operates with free air convection, so no forced cooling is required, reducing noise and maintenance. For installation, ensure adequate clearance around the unit for heat dissipation.