MEAN WELL RD-125B 125W Dual Output AC/DC Power Supply 5V 15A and 12V 8A Enclosed Chassis Mount

The RD-125B stands apart from typical power supplies by delivering two independent, tightly regulated DC outputs—5 V and 12 V—from a single compact enclosed chassis. This dual-output design eliminates the need for two separate converters in many industrial and automation systems, saving space, wiring, and cost. With a full 125 W of continuous power and a universal 88–264 VAC input, it is equally at home on a European 230 V line or a North American 120 V circuit, without any manual switching.

Highlights

• Dual outputs: +5 VDC up to 15 A and +12 VDC up to 8 A, total 125 W
• Wide input range: 88–264 VAC or 125–373 VDC, 47–63 Hz
• Protections: short circuit, overload, over voltage on both channels
• Free air convection cooling – no fan, silent operation, no moving parts
• Enclosed metal case, chassis mount with screw terminals
• CH1 output voltage adjustable ±10% via built-in potentiometer
• Low ripple and noise: 80 mVp-p on 5 V, 120 mVp-p on 12 V
• Safety approvals: UL60950-1, TUV EN60950-1, CB, CE

In daily use

In a typical control cabinet, the RD-125B powers logic circuits, sensors, relays, and small motors simultaneously. The 5 V rail handles microcontrollers and digital electronics, while the 12 V rail drives fans, solenoids, or analog interfaces. Because it is convection cooled, it can be mounted in sealed enclosures or dusty environments where fan-cooled units would fail. The ±10% adjustment on the 5 V output allows fine-tuning for voltage drop in long cable runs. With a hold-up time of 16 ms at full load, it rides through brief mains interruptions, preventing reboots of connected equipment.

Full specifications

• Brand: MEAN WELL
• Model: RD-125B
• MPN: RD-125B
• EAN: 4021087014960
• Power output: 125 W
• Output 1: +5 VDC, 0–15 A
• Output 2: +12 VDC, 0–8 A
• Input voltage: 88–264 VAC / 125–373 VDC
• Input frequency: 47–63 Hz
• Efficiency: 80% typical
• Ripple & noise: 80 mVp-p (5 V), 120 mVp-p (12 V)
• Setup, rise time: 800 ms, 50 ms at 230 VAC full load
• Hold up time: 16 ms at 230 VAC full load
• Operating temperature: -25 to +70 °C
• Cooling: Free air convection
• Mounting: Chassis mount, enclosed
• Protections: Short circuit, overload, over voltage
• Safety standards: UL60950-1, TUV EN60950-1, CB, CE

Final note

For engineers and integrators who need reliable dual-rail DC power in a rugged, fanless package, the RD-125B is a proven workhorse. Its conservative ratings and full protection suite ensure long service life even in demanding industrial environments.