Power adapter/inverter Mean Well RSD-300D-5 — 300 W, Input 67.2–143 V, Output 5 V, RoHS

Mean Well RSD-300D-5 is a compact DC-DC enclosed converter designed for industrial and railway power systems. The module provides a fixed 5 V output at up to 300 W total power, accepting a wide DC input range suitable for vehicle and trackside applications. It meets EN50155 railway standard requirements and includes reinforced isolation between input and output to support safe operation in demanding environments. The unit is RoHS compliant and comes in a slim housing with dimensions 97 × 216 × 40 mm, making it appropriate for DIN-rail or cabinet installation where a stable 5 V supply is needed.

Advantages

The RSD-300D-5 offers a wide input voltage window that covers common railway and industrial DC systems, enabling direct connection to battery strings or intermediate DC buses without extra converters. With an output capable of delivering up to 42 A at 5 V, it supports high-current loads while keeping heat dissipation manageable in a compact enclosure. The device features 4000 Vdc input-to-output isolation for enhanced safety and electromagnetic compatibility in mixed-signal installations. Compliance with EN50155 and RoHS ensures suitability for transportation applications and adherence to environmental restrictions.

Suitable for

• Railway onboard power conversion and trackside power supplies
• Industrial control cabinets and DIN-rail systems
• Battery-fed DC distribution and vehicle power systems
• High-current 5 V loads such as controllers, communication equipment, and I/O modules

Key specifications

• Output voltage: fixed 5 V DC
• Maximum output current: up to 42 A (total output power ~300 W)
• Input voltage range: wide DC input suitable for 57.6–154 V DC systems
• Isolation: 4000 Vdc input-to-output isolation
• Standards: designed to meet EN50155 railway requirements
• Protection features: built-in protection against overload and short circuit (as typical for enclosed converters)
• Form factor: enclosed module with compact dimensions 97 × 216 × 40 mm

How to use

Install the RSD-300D-5 in an appropriate cabinet or onto a DIN rail according to the mechanical instructions supplied by the manufacturer, ensuring adequate airflow and clearance around the module. Connect the DC input to the appropriate voltage bus within the specified input range and observe correct polarity. Route the 5 V output to the load circuits, verifying that combined load current does not exceed the rated 42 A. Confirm earthing and grounding practices per system requirements and perform initial power-up checks while monitoring output voltage and temperature.

Recommendations

For reliable long-term operation, maintain ambient temperatures and ventilation within the manufacturer’s specified limits, avoid exposing the unit to excessive vibration or moisture, and use proper fusing on the input side. For railway installations, follow applicable EN50155 installation and maintenance practices and validate the unit under real operating conditions before commissioning.