High-performance low-voltage circuit protection engineered for commercial grids, PV microgrids, and industrial automation.
In modern industrial electrification, smart building management, and grid-scale renewable energy integration, the reliability of low-voltage distribution switchgear remains non-negotiable. As global power networks transition toward decentralized microgrids, high-density EV charging hubs, and continuous data center topologies, the demand for high-breaking-capacity Air Circuit Breakers (ACB), Molded Case Circuit Breakers (MCCB), and Miniature Circuit Breakers (MCB) has experienced an unprecedented technological shift.
Rooted in Yueqing, Wenzhou—universally recognized as the "Capital of Electrical Appliances in China"—Wenzhou OFA Electrical Technology Co., Ltd. (founded in 2013) stands at the forefront of this industrial evolution. Operating under proprietary brands such as "OFA", the company combines deep electromechanical engineering research with advanced digital lean manufacturing to produce IEC and CE-compliant power control devices.
Rated as a Tax Credit Grade A Enterprise for seven consecutive years, OFA operates on an unyielding principle of transparent, zero-defect engineering. By bridging standardized bulk manufacturing with flexible custom OEM/ODM development, OFA provides global system integrators and EPC contractors with certified protective gear designed for high breaking capacities (Icu/Ics up to 100kA), thermal endurance, and seamless telemetry integration.
Understanding the internal electrodynamic forces driving low-voltage protective devices.
When short-circuit currents surge through breaker contacts, magnetic blowout coils force the electric arc into an arc splitter chamber (arc chute). The copper-plated steel plates split, cool, and extinguish high-temperature ionized gas within milliseconds (< 5ms), preventing structural cabinet explosion.
Replacing traditional bimetallic strips, modern Air Circuit Breakers (ACB) utilize DSP-driven Electronic Trip Units (ETU). These afford precise selectively coordinated trip curves: L (Long-Time Overload), S (Short-Time Delay), I (Instantaneous Short Circuit), and G (Ground Leakage) to eliminate system-wide blackouts.
To withstand repeated breaking cycles without contact welding, OFA circuit breakers utilize Silver Tin Oxide (AgSnO2) composite contact tips. This eco-friendly alternative to Silver Cadmium Oxide provides superior thermal anti-welding properties and low contact resistance over thousands of switching operations.
| Breaker Category | Rated Current Range (In) | Ultimate Breaking Capacity (Icu) | Primary Application Segment | Core Protection Mechanisms |
|---|---|---|---|---|
| Air Circuit Breaker (ACB) | 630A to 6300A | 50kA to 120kA | Main Low-Voltage Incomers, Data Centers, Heavy Industry | Overload, Selective Short Circuit, Earth Leakage, Harmonics, Telemetry |
| Molded Case Breaker (MCCB) | 16A to 1600A | 25kA to 100kA | Sub-distribution Switchboards, Motor Control Centers (MCC) | Thermal-Magnetic Overload, Magnetic Short-Circuit, Shunt Trip |
| Miniature Breaker (MCB) | 0.5A to 125A | 4.5kA to 15kA | Final Distribution Panels, Commercial & Residential Circuits | Bimetallic Thermal Overload, Solenoid Instantaneous Short Circuit |
| Residual Current Breaker (RCBO) | 6A to 80A | 6kA to 10kA | Personal Life Protection, Wet Environments, Telecom Power | Combined Overload, Short Circuit & High-Sensitivity Earth Leakage (30mA) |
| Isolator Switch (IS) | 32A to 125A | N/A (Load Break Only) | Main Service Isolation, Solar PV String Isolators | Positive Contact Indication, High Dielectric Isolation Distance |
Wenzhou OFA Electrical Technology Co., Ltd. manufactures an extensive range of power distribution components engineered for demanding operating environments.
Designed to protect feeders from 15A to 1600A. OFA’s MCCB portfolio includes the BA88 Electronic Series, DCM1 Series, DCOF1 Series, OFM1 Series, OFBLT Series, OF1 Series, and the flag-ship OFA-M1 Series (400A). Features include adjustable thermal settings, rotary operating handles, and auxiliary contact blocks for remote monitoring.
Engineered for DIN-rail mounting in distribution boards. Product series encompass OF6KA Series, OF10KA C65 Series, OFAFT Series, OFD4Z7 Series, OFDL Series, OFDP, OFDZ47 Series, OFEU Series, OFKL Series, OFKL-NXB Series, OFL7 Series, OFL8 Series, OFNC Series, OFPF Series, and OFP Series.
The flagship OFW1 Intelligent Universal Circuit Breaker Series acts as the central brain of low-voltage switchgear. Designed for main power distribution systems, the OFW1 features modular draw-out or fixed designs, intelligent controllers with LCD displays, protocol gateway interfaces (Modbus-RTU, Ethernet), and high short-time withstand current (Icw).
Guarding personnel against electric shock and preventing electrical fires caused by insulation faults. Series include OFAP6-AC, OFDPN, OFDX, OFGX, OFID, OFPM, OFC Series, OFKL-80A, NB1L Series, OFMIN, OFOM, and OFR1 Series. Available in Type AC, Type A, and Type B (DC-sensitive) options.
Specially constructed for high-voltage direct current applications up to DC 1500V. Featuring magnetic arc-extinguishing channels to safely interrupt ungrounded DC current in solar PV combiner boxes, Battery Energy Storage Systems (BESS), and EV charging stations, such as the OF1-125/PV DC MCCB.
Combining non-automatic load breaking with complete circuit disconnection security. Includes OFIS-125A Series, OFIS-BH Series, and OFIS-DS Series. Designed with visible break windows and lock-out/tag-out (LOTO) features to ensure safety during maintenance operations.
Leveraging the Yueqing Electrical Cluster for Unmatched Production Scalability and Quality Control
Located in Yueqing, Wenzhou—the nerve center of global electrical switchgear manufacturing—OFA benefits from an hyper-integrated supply chain ecosystem. Within a 10-kilometer radius, high-precision tooling, silver contact sintering, flame-retardant BMC/PBT plastic moulding, and copper stamping are seamlessly coordinated, drastically reducing procurement lead times and component costs.
Delivering reliable circuit protection across diverse sector environments.
Providing robust short-circuit motor protection and selective tripping for factory distribution lines, ensuring heavy inductive loads (pumps, compressors, conveyors) run continuously without nuisance tripping.
Specialized high DC-voltage circuit breakers (DC 1000V/1500V) designed to manage bi-directional current flows and extinguish difficult direct-current arcs in solar inverter stations and energy storage containers.
Deploying high-sensitivity RCBOs and smart ACBs with automatic transfer switches (ATS) to safeguard vital infrastructure, medical equipment, and occupant safety with zero tolerance for power interruptions.
Essential engineering considerations when sourcing circuit protective equipment from China manufacturers.
When specifying low-voltage equipment, understanding the regulatory boundaries is critical:
OFA provides end-to-end support for international brand owners and panel builders:
See how clients worldwide depend on OFA electrical switchgear for uninterrupted power.
"As a system integrator, our company has collaborated with OFA on several industrial automation projects in Central Europe. Their product range is remarkably comprehensive, covering everything from protective relays to ACB communication gateways. Product quality is consistent, eliminating commissioning hassle."
"We purchased OFA's intelligent power monitoring MCCBs and ACBs to upgrade the distribution switchgear in our manufacturing workshop. The installation was straightforward, and they have operated flawlessly for over two years under continuous peak loads."
"Our utility-scale solar PV project in South America required reliable DC 1000V circuit protection that could withstand ambient outdoor heat. OFA's DC Molded Case Circuit Breakers met our technical specs at competitive pricing. Excellent engineering support."
Expert engineering answers regarding procurement, standards, design, and factory partnerships.
Explore additional specialized residual current devices, miniature breakers, and photovoltaic protection units.
Whether engineering a complex multi-energy industrial plant or seeking high-volume OEM distribution switchgear, Wenzhou OFA Electrical Technology Co., Ltd. brings 13+ years of expertise to your supply chain.
OFA Electrical
