--- title: "Open Frame Power Supply Selection Guide for Industrial OEMs" url: https://everspower.com/open-frame-power-supply-selection-guide-for-industrial-oems/ date: 2026-09-25 modified: 2026-10-25 lang: en author: "EVEVSPOWER Engineering Team" description: "Open frame power supplies come in two main styles: board-mount AC-DC converters for compact ITE systems up to roughly 100W, and connector-based open frame modules from 100W to 500W. Board-mount..." categories: - "Power Conversion Basics" tags: - "Acdc" - "Supply" - "Supply Acdc" image: https://everspower.com/wp-content/uploads/2026/08/everspower-3cd0c331.jpg word_count: 1053 --- # Open Frame Power Supply Selection Guide for Industrial OEMs Open frame power supplies come in two main styles: board-mount AC-DC converters for compact ITE systems up to roughly 100W, and connector-based open frame modules from 100W to 500W. Board-mount units save volume and lower per-unit costs, while connector formats offer easier maintenance and better lifecycle value for modular machinery. Choosing the correct power architecture often determines whether an industrial machine runs reliably for years or fails during commissioning. When space is tight and cooling airflow is guaranteed, an open frame power supply becomes the default choice for many equipment designers. These bare-board assemblies strip away enclosures to maximize watt-density and minimize cost, but they also shift thermal and safety responsibilities onto the system integrator. Because open frame supplies are unshielded noise sources, integrators must also address Electromagnetic Compatibility (EMC), including conducted and radiated emissions as well as immunity, through appropriate filtering and shielding strategies. Furthermore, meeting safety standards typically requires installing an insulating sheet or barrier between the supply and any metal chassis to prevent dielectric breakdown. Understanding these mechanical, electrical, and regulatory trade-offs between different open-frame styles prevents costly redesigns later in production. ## Which Board-Mount Architectures Suit Compact ITE Systems? ![Detailed cross-section rendering of board mount AC-DC converter highlighting thermal path through PCB copper](https://everspower.com/wp-content/uploads/2026/08/everspower-6157b891.jpg) When engineers search for a compact energy source for information technology equipment (ITE), the board mount AC-DC converter usually sits at the top of the list. These units solder directly to the main PCB, eliminating harnesses and reducing assembly labor. For low voltage AC-DC power supply needs ranging from a few watts up to roughly 100W, this direct-attach approach saves significant volume. Why choose direct PCB integration over other methods? Primarily, it reduces impedance and noise. By placing the conversion stage millimeters from the load, you minimize voltage drops and susceptibility to radiated interference. In high-speed digital circuits or sensitive sensor interfaces, this proximity matters. However, the trade-off is serviceability. If the module fails, rework requires desoldering multi-pin components through plated holes. This makes board-mount formats ideal for sealed, long-life products where field repair is not anticipated. Thermal management in these footprints typically relies on conduction and natural convection within the host enclosure, though some models in the higher end of this power range incorporate metal baseplates designed for conduction to an external chassis. Designers must ensure copper pours and thermal vias are adequate to spread heat away from the converter’s baseplate. Without an external fan, the ambient temperature inside the chassis can rise quickly, potentially derating the unit below its nominal specification. Always validate thermal performance in the final mechanical configuration, not just on a test bench. ## How Do Connector-Based Open Frame Modules Enable Flexible Integration? Larger industrial systems often demand more flexibility than a soldered joint can provide. An open frame AC-DC module with wire leads or quick-connect terminals addresses this need. These connector-based supplies typically cover higher power levels, from 100W to 500W, where board-mount form factors become impractical due to weight and heat concentration. The primary advantage here is mechanical decoupling. The power stage mounts to the chassis via standoffs, while Molex or JST connectors link it to the control board. This separation simplifies manufacturing: sub-assemblies can be tested independently before final integration. It also eases maintenance. A technician can swap a faulty unit in minutes without touching a soldering iron. For OEMs building modular machinery or equipment requiring field upgrades, this format offers superior lifecycle value. Sourcing these larger formats requires attention to creepage and clearance distances. Unlike encapsulated modules, open frames expose live components. System integrators must maintain safe spacing from grounded metalwork and user-accessible panels. IEC/UL 60950 and newer 62368-1 standards define specific thresholds for hazardous energy; exceeding 240VA or storing more than 20J demands additional safeguards. When evaluating a potential supply supplier, verify that their design documentation includes clear keep-out zones and insulation coordination data. EVEVSPOWER supports both integration philosophies across our extensive catalog. As an AC-DC converter manufacturer with over 1,000 models spanning 1W to 5000W, we provide options from compact board-mount units to chassis-ready open frames. Our [Dongguan](https://everspower.com/about/) facility produces 10,000+ units daily with MOQs as low as 10 pieces, enabling rapid prototyping and scalable production for diverse industrial applications. ## What Are Frequently Asked Questions About Open Frame Power Conversion? ### How do I determine if an open frame supply is safe for my enclosure? Safety depends on your system-level design, not just the component certification. Open frame units assume the end-product provides secondary protection. You must verify that internal barriers, grounding straps, and label warnings meet the relevant safety standard for your market. If your enclosure is plastic or has ventilation slots near live parts, additional insulating sheets or potting may be necessary. Always request the CB report and installation manual from your manufacturer to confirm compliance boundaries. ### What causes premature failure in board-mount converters? Thermal cycling is the most common killer. Repeated expansion and contraction stress solder joints, especially under heavy ceramic capacitors or transformers. To mitigate this, use compliant pin headers or add adhesive fillets at component edges. Also check input surge ratings; industrial environments often see transients exceeding 1kV. If your site has poor mains conditioning, select a unit rated for IEC 61000-4-5 Class 3 or 4, or add external MOVs and gas discharge tubes coordinated with the PSU’s internal protection to prevent mismatched let-through voltages or nuisance tripping. ### Can I use an open frame supply in high-vibration environments? Yes, but with precautions. Solder-only attachments fatigue quickly under vibration. For board-mount types, specify through-hole pins rather than surface-mount pads, and consider conformal coating to dampen resonance. Connector-based modules should use locking terminals or positive-retention housings. Standoff mounting points must include nylon washers or elastomeric grommets to isolate mechanical shock. Test prototypes against IEC 60068-2-6 sine sweep or random vibration profiles matching your actual operating environment. ### How does pricing scale between board-mount and connector formats? Generally, board-mount units have lower per-unit costs at high volumes due to automated pick-and-place assembly. Connector-based supplies carry added expense for wire termination, housing hardware, and manual labor. However, total cost of ownership may favor connector types if field service frequency is high. Evaluate your expected failure rate, warranty terms, and repair logistics alongside the bill-of-materials price. Many buyers find that paying slightly more upfront for serviceable designs reduces lifetime support costs significantly. For detailed specifications or custom requirements tailored to your application, reach out to our engineering team at allan@everspower.com or visit www.everspower.com.