High Power Demand: How the Vox Power EIRE300 Solves the Constraint

1. Real World Design Constraint

This blog is written for design engineers and system architects who are integrating AC-DC power supplies into space constrained, compliance driven equipment. This includes medical device engineers, industrial automation designers, test and measurement teams, and OEM control system developers who are responsible for both electrical performance and overall system reliability.

If you are selecting a power supply with a 4 x 2 power supply form factor and balancing power density, thermal margin, leakage current limits, and global safety approvals, this discussion is for you. It is particularly relevant for engineers designing platforms that must serve multiple markets such as medical and industrial, where 2 MOPP isolation, efficiency, and mechanical constraints all influence architecture decisions.

Any engineer responsible for power supply selection, enclosure temperature management, compliance strategy, or long term field reliability will benefit from this analysis of where the Vox Power EIRE300 fits in real system design.

2. Where the EIRE300 Fits

The Vox Power EIRE300 Series of open frame power supplies deliver 300W of power within the compactness of a 4” x 2” footprint, capable of 375W peak power with fan cooling and 200W at convection cooling at 115Vac. It is designed for systems where board space is constrained but several hundred watts are required.

The series supports standard output voltage options including 12Vdc, 24Vdc, 36Vdc, and 48Vdc with a wide adjustment range. Moreover, efficiency reaches up to 95%, reducing heat generation and simplifying thermal design.

Designed for -40~+70°C, the EIRE300 series supports both convection cooled systems and forced air cooled systems. Its design utilizes long-life capacitors, conformal coating, and a calculated MTBF of over 500k hours for maximum reliability and performance.

System level features include 2 x MOPP isolation, low leakage current, remote sense, AC OK, and a 0.5A auxiliary fan supply output. The series meets IEC/UL60601-1, IEC/UL62368-1, and EMC Class B requirements, supporting both medical power supply and industrial power supply system designs.

With that said, the following sections will dive into EIRE300’s key design features, including power density and peak capability, efficiency and thermal implications, and isolation and leakage characteristics, showing how the features impact system integration and performance.

3. Power Density and Peak Capability

The Vox Power EIRE300 delivers 300W in the compact 4” x 2” footprint, achieving a power density of 37.5W/in³, with a peak output of 375W for 1 second.

The compact and high density design allows the supply to fit into tight enclosure spaces while delivering all required power from a single source. The peak output capability enables the system to handle transient loads such as motor startups or current inrush without triggering over current protection. This allows engineers to size the power supply for continuous operation while maintaining extra headroom for short term peaks typical of inductive loads.

4. Efficiency and Thermal Implications

The Vox Power EIRE300 operates at up to 95% efficiency, minimizing conversion losses and reducing temperature rise within enclosures and systems. At a maximum load of 300W, this corresponds to roughly 16W of heat loss, which is significantly lower than comparable power supplies given the same form factor and output.

The reduced heat dissipation, combined with the compact form factor, enables smaller enclosure designs and lower cooling requirements, making the series valuable for space constrained systems.

Some thermal considerations to keep in mind is that the output of the EIRE300 depends on the thermal design of the unit. Convection cooled operation supports up to 200W at 115Vac while forced air operation can reach 300W, provided that there is adequate airflow (10.2 CFM). Appropriate derating according to the manufacturer should be followed for reliable operation. In practice, engineers should always validate thermal performance in the final enclosure.

In practice, engineers should always validate thermal performance in the final enclosure.

5. Safety and Isolation Strategy

The Vox Power EIRE300 series is certified to IEC/UL 60601-1 for medical equipment and IEC/UL 62368-1 and IEC/UL 61010-1 for industrial and laboratory systems. From a design standpoint, these certifications allow engineers to use one platform across both medical and industrial builds, simplifying global compliance planning and reducing redesign risk between product lines.

In addition, the series features 2 x MOPP isolation with 4000Vac input to output isolation. This reinforced isolation barrier is critical for BF-rated medical applications helping ensure patient safety while also protecting downstream electronics from high voltage transients or fault conditions on AC mains.

6. Leakage Current and Multi Power Supply Systems 

The Vox Power EIRE300 is designed with low leakage current, which becomes increasingly important in systems that incorporate multiple power supplies where leakage current is additive. In medical and precision electronic equipment, leakage from each supply contributes to the total system leakage, which must remain within the limits defined by the applicable safety standards.

By maintaining low leakage at the power supply level, engineers can integrate more units within the same system without approaching system level limits. This simplifies system design and reduces the need for additional mitigation measures during testing and certification.

7. Integration Features

Additionally, the Vox Power EIRE300 includes several features that simplify system level integration:

• Remote Sense: Compensates for voltage drops across load connections, ensuring accurate voltage levels at point of load.

  AC OK Signal: Provides a status signal of AC input, enabling fault response and system level monitoring.

  Auxiliary Fan Output: Allows external fans to be driven directly from the power supply by providing a 0.5A auxiliary output.

  Class I and Class II: Compatible with both grounded (Class I) and ungrounded (Class II) installations.

  EMI Compliance (EN55032/EN55035, Class B): Meets conducted and radiated emission limits for Class B standard, supporting integration into sensitive electronic and medical equipment without additional filtering.

8. Application Examples

The Vox Power EIRE300 is engineered for systems that demand compact, reliable, and high efficiency power. Its combination of thermal performance, reinforced isolation, and compliance with medical and industrial standards make it a strong fit across a variety of real world applications. Some practical examples include the following:

9. Closing Design Guidance

The Vox Power EIRE300 allows engineers to deliver up to 300W output within strict mechanical constraints, supporting both convection and forced air thermal designs. By combining high efficiency, reinforced isolation, low leakage current, and system integration features into a single compact platform, it reduces the need for multiple components and simplifies system level design.

This makes the Vox Power EIRE300 well suited for applications where space, thermal margin, and compliance and flexibility interest, allowing engineers to focus on optimizing the overall system rather than managing separate power, safety, and thermal considerations.