The Overvoltage Category (OVC) is used to define the level of transient overvoltage a device may be exposed to, typically caused by events like lightning strikes, grid fluctuations, or unstable power sources.

According to IEC 60664-1, four OVC categories are defined:
● OVC I: Signal-level circuits or protected internal electronics
● OVC II: Standard electrical equipment connected to wall outlets or similar points (e.g., PCs, TVs)
● OVC III: Equipment permanently connected to the fixed installation (e.g., control panels, industrial automation)
● OVC IV: Equipment connected directly to the building’s mains power source or primary distribution grid (e.g., infrastructure-level distribution systems, utility meters)

Most building equipment falls under OVC II or OVC III, but only OVC IV certified products can safely operate in primary power environments, offering the highest level of surge immunity.

In real-world industrial and energy infrastructure, power systems are often exposed to high-energy transients, grid fluctuations, or direct mains connections, especially in environments like:
● Industry control cabinets
● Smart meters and energy gateways
● EV charging stations and control systems
● Renewable energy interfaces (solar/wind)
● Industrial automation and field devices
● Power gateways and substation monitoring
● Outdoor energy control and building service panels

These scenarios demand power supplies that don’t just meet basic isolation—they must survive extreme surge conditions and comply with OVC III/IV standards for safety and global deployment.

Designing power systems for Overvoltage Category III and IV environments introduces significant technical and regulatory challenges that go far beyond standard ITE or consumer-grade applications. Engineers must ensure systems can withstand high-energy surges, direct grid connections, and unpredictable transient voltages—all while meeting strict international safety standards.

Key Challenges Include:
● Surge Immunity Requirements
Devices must handle large overvoltage transients (up to several kilovolts) caused by lightning strikes, switching surges, or unstable utility power.
● High Isolation Demands
Reinforced insulation is required—often up to 4300–5700VAC—to ensure user safety and prevent system damage.
● Space Constraints vs. Protection
Traditional solutions require bulky filters, varistors, or protection circuitry—challenging when board space is limited.
● Global Compliance
Navigating certifications like IEC 62368-1, 60335, 61558, and OVC-specific requirements adds to testing complexity and time-to-market.
● System Integration Complexity
Meeting EMC compliance in high-surge environments without external filtering is difficult, especially in compact designs or field-deployed systems.

At ARCH, we understand the growing need for compact, compliant, and surge-resistant power modules in high-risk electrical environments. That’s why we developed a full line of certified OVC III and OVC IV AC-DC power supplies—engineered from the ground up to solve real-world design pain points.

● Certified Surge Immunity
Our OVC III & OVC IV modules are certified according to IEC 62368-1 and built to endure severe electrical transients, delivering reinforced insulation up to 5700VAC. They’re ready to deploy in systems subject to direct connection to utility mains or primary power distribution.
● Compact Form Factor, No External Protection Needed
Unlike bulky discrete designs, ARCH’s power supplies integrate surge resilience into a space-saving form factor, eliminating the need for additional surge suppression components. Our OVC III & IV power supplies also meet EMC requirements without external filters, saving valuable board space and BOM cost.
● Ready for Harsh Environments
With wide operating temperature ranges (up to -40°C to +85°C) and altitude ratings of up to 5000m, ARCH power supplies are ideal for rugged outdoor, industrial, or grid-edge deployments.

With ARCH’s OVC III & IV power supplies, designers no longer need to over-engineer their systems or source complex custom solutions. We provide fully certified, compact, and reliable AC-DC power modules and switching power supplies that simplify certification, streamline system design, and reduce overall cost, while enabling faster time-to-market.