Mean Well LOP-400-54 400W 5"×3" Low Profile Open Frame Power Supply 54V

The LOP-400-54 is a 400W open frame AC-DC power supply with a nominal 54V DC output. Its rated output current is 4.75A. This model is designed for applications that need a compact low-profile power source with higher-voltage DC output.

This model uses a 5 x 3 inch footprint and has a low profile height of 27.5mm. The published dimensions are 127 x 76.2 x 27.5mm. That makes it suitable for equipment where internal space and vertical clearance are limited.

The LOP-400-54 is specified with IEC/EN/UL 62368-1 and IEC60601-1 related approvals, and the description states 2 x MOPP suitability for BF medical applications. It also lists household and industrial safety standards, which supports use across multiple regulated equipment categories. Buyers should still confirm the full end-product compliance requirements for their specific system.

Yes. The LOP-400-54 is rated for 250W under convection cooling and up to 400W with 23CFM forced-air cooling. It also includes a built-in 12V/0.5A auxiliary output for an external fan.

This model is rated for operation from -40°C to +80°C, subject to the manufacturer's derating guidance. It is also specified for operating altitude up to 5000 meters. Those specs make it a stronger fit for demanding industrial environments than many general-purpose open frame supplies.

The LOP-400-54 includes short circuit, overload, overvoltage, and overtemperature protection. The overload specification is 105 to 150% of rated output power, with hiccup protection after 3 seconds and automatic recovery after the fault is removed. Overvoltage and overtemperature protection shut down the output and recover after conditions return to normal or power is cycled, depending on the condition.

Yes. Mean Well specifies efficiency up to 95% for this series and no-load power consumption below 0.5W. That combination is useful in equipment where thermal performance and energy usage are important selection factors.