Explore high-performance Miniature Circuit Breakers manufactured under strict ISO9001 and IEC standards for global industrial applications.
In modern commercial, industrial, and residential electrical infrastructures, demand for ultra-reliable low-voltage distribution switchgear has shifted dramatically. Global supply chains now demand unprecedented breaking capacity, thermal stability, miniaturized footprints, and seamless integration with intelligent edge control monitoring systems.
As a core cornerstone product from Wenzhou OFA Electrical Technology Co., Ltd., the OFNC Series Miniature Circuit Breaker (MCB) represents over a decade of continuous precision engineering. Manufactured in Yueqing, Wenzhou—the renowned Capital of Electrical Appliances in China—the OFNC series serves as the primary barrier against overcurrents, sustained overloads, and high-energy short-circuit faults.
Comprehensive breakdown of mechanical tripping mechanisms, contact metallurgy, arc suppression, and thermodynamic performance.
The OFNC series features a 12-plate arc chute assembly made of high-grade copper-plated steel. When a short-circuit fault occurs, the electromagnetic force rapidly drives the electrical arc into the chute, cooling and splitting it into micro-arcs within 3 to 5 milliseconds.
Constructed with high-content silver-graphite (AgCdO/AgZnO) stationary and moving contacts, the OFNC series prevents contact welding during extreme fault currents while maintaining minimal contact resistance and minimal temperature rise.
The outer housing is molded from high-density, anti-tracking polycarbonate and polyamide materials. It withstands glow-wire tests up to 960°C, providing exceptional structural integrity, seismic resilience, and electric shock protection.
| Parameter Standard | Technical Requirement / Specification | OFNC Series Performance Level |
|---|---|---|
| Rated Operational Voltage (Ue) | AC 230V / 400V (50/60 Hz) | High Dielectric Strength Insulation (>2500V AC) |
| Rated Current Range (In) | 1A, 2A, 3A, 4A, 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A | Full Current Range Available Across 1P, 2P, 3P, 4P |
| Ultimate Short-Circuit Capacity (Icu/Icn) | IEC/EN 60898-1: 6,000A / 10,000A | Class 3 Energy Limiting Category |
| Tripping Characteristics | Type B (3-5 In), Type C (5-10 In), Type D (10-14 In) | Calibrated Thermal-Magnetic Release Mechanisms |
| Electrical / Mechanical Endurance | IEC 60898-1 Standard Cycles | 10,000 Electrical Cycles / 20,000 Mechanical Cycles |
| Protection Class & Mounting | IP20 (IP40 in enclosure), 35mm DIN Rail | Modular Standard Width (18mm per Pole) |
A trusted professional manufacturer and supply chain partner rooted in China's low-voltage electrical hub.
Founded in 2013, Wenzhou OFA Electrical Technology Co., Ltd. has established itself as an authoritative supplier of distribution switchgear, circuit breakers, and control equipment. Located in Yueqing, Wenzhou—the heart of China’s electrical equipment industry—our modern production facilities utilize automated assembly lines, digital inspection stations, and rigorous full-process type testing.
Our firm commitment to transparent, compliant, and high-quality operation has earned us the Tax Credit Grade A designation for seven consecutive years. With over 96 skilled production workers and 13+ years of specialized engineering experience, we partner with more than 780 international clients across power utilities, commercial construction, industrial automation, and renewable energy sectors.
Precision manufacturing minimizing out-of-factory defect rates.
100% routine inspection on mechanical life and temperature rise.
Handling high-volume urgent orders with secure export packaging.
Deploying OFNC series and comprehensive distribution protection across modern critical infrastructure.
Protects string inverters, battery energy storage systems (BESS), and DC-AC combiner boxes against harmonic surges, backfeeds, and electrical faults in decentralized clean energy installations.
Integrates into PLC cabinets, motor control centers (MCC), and robotics production lines where high mechanical endurance and rapid fault isolation are vital to prevent downtime.
Provides high breaking capacity isolation for critical rack Power Distribution Units (PDUs) and uninterruptible power supply (UPS) systems, ensuring continuous server uptime.
Serves as main and sub-distribution protection in high-rise HVAC panels, elevator power systems, and intelligent lighting control cabinets.
Protects AC charging piles and DC fast-charging stations from localized overload currents and ground leakage fault hazards under high duty cycles.
Applied in municipal power distribution boxes, street lighting grids, and transportation control networks with severe environmental stability requirements.
In addition to the flagship OFNC Series, OFA manufactures complete low-voltage switchgear components.
Designed to make, carry, and break currents under normal and abnormal conditions up to 1600A. Series include BA88, DCM1, DCOF1, OFM1, OFBLT, OF1, and OFA-M1.
Compact terminal protection. Series include OF6KA, OF10KA C65, OFAFT, OFD4Z7, OFDL, OFDP, OFDZ47, OFEU, OFKL, OFKL-NXB, OFL7, OFL8, OFNC, OFPF, and OFP.
High-capacity core protection with intelligent microprocessor controllers. Series features OFW1 Intelligent Universal Circuit Breaker up to 6300A.
High-sensitivity earth leakage and shock protection. Series include OFAP6-AC, OFDPN, OFDX, OFGX, OFID, OFL7, and OFPM.
Innovatively integrates overload, short-circuit, and earth leakage in a single pole width. Series include OFC, OFKL-80A, NB1L, OFMIN, OFOM, and OFR1.
Combines robust isolation capabilities with structural durability. Series include OFIS-125A, OFIS-BH, and OFIS-DS.
How Wenzhou OFA Electrical Technology is pioneering intelligent edge power management.
The low-voltage electrical protection sector is undergoing a paradigm shift. Traditional MCBs rely purely on passive thermal-magnetic movement. OFA’s next-generation product technology roadmap integrates micro-sensors and IoT communication modules (Modbus-RTU, RS485, wireless Matter/Zigbee) directly into the modular rail footprint.
Phase 1 (Established): Standardization of high breaking capacity 6kA/10kA MCB & RCCB platforms.
Phase 2 (Current): Multi-functional RCBO integration & ISO9001 full inspection automation.
Phase 3 (Future): Smart IoT Breakers, cloud-based predictive maintenance SCADA platforms.
See why global industry leaders and EPC contractors rely on OFA for their electrical systems.
"We purchased OFA's intelligent power monitoring devices to upgrade the power distribution system in our old workshop. The installation and setup were simpler than expected, and integration went smoothly. Most importantly, they have been running stably for over a year."
"Deploying OFA's energy efficiency management system for several office buildings we manage was a wise decision. The system helped us gain detailed insights into electricity usage in different areas and achieve clear energy savings."
"Our PV project required reliable communication management and data acquisition equipment. OFA's products met our core needs at a reasonable price and adapted to our local outdoor environment perfectly."
"As a system integrator, our company has collaborated with OFA on several industrial automation projects. Their comprehensive range simplifies procurement and integration. Quality is consistent, reducing on-site commissioning issues."
Expert insights regarding procurement, OEM/ODM customization, compliance, and technical support.
Complete your power distribution system with our extensive range of high-performance components.
OFA Electrical