Explore our flagship modular circuit breakers engineered for exceptional breaking capacity, thermal endurance, and rapid fault isolation.
Understanding the transition from traditional Alternating Current (AC) protection to modern High Voltage Direct Current (HVDC) power architecture.
Unlike Alternating Current (AC) systems which cross zero voltage twice per cycle (allowing natural arc extinguishing during fault isolation), Direct Current (DC) maintains continuous current magnitude. When contacts separate under high voltage DC loads (e.g., 500V DC to 1500V DC), an intense electrical plasma arc is sustained. OEM High Voltage DC Circuit Breakers engineered by OFA utilize permanent magnetic blowout technology and specialized arc chute splitter plates to stretch, cool, and extinguish DC arcs within milliseconds.
Modern Battery Energy Storage Systems (BESS) present short-circuit discharge profiles with extremely low time constants (L/R) and enormous peak fault currents (up to tens of kiloamperes). Standard AC switchgear fails under these stress profiles due to thermal contact welding. OFA’s specialized High Voltage DC breakers feature silver-alloy arc runner contacts and optimized thermal-magnetic trip units specifically calibrated for rapid DC fault breaking without degradation.
In high-voltage solar generation and battery back-feed scenarios, current direction can reverse during system faults or charging/discharging cycles. Traditional DC breakers require strict directional wiring. OFA’s advanced OEM non-polarized High Voltage DC circuit breakers incorporate dual-direction magnetic arc-guidance systems, eliminating installation wiring mistakes and ensuring bidirectional overload and short-circuit protection.
Attempting to use AC-rated Miniature Circuit Breakers (MCBs) or Molded Case Circuit Breakers (MCCBs) in DC applications above 60V without voltage derating or multi-pole series cascading results in catastrophic arc flash failures. Direct current arcs lack zero-crossing points, requiring up to 4x larger arc chambers, specialized magnetic arc chutes, and non-linear arc runner geometry to force dielectric recovery.
Founded in 2013 in Yueqing, Wenzhou, OFA delivers trusted distribution switchgear and control equipment engineered for reliability, safety, and operational longevity.
Wenzhou OFA Electrical Technology Co., Ltd. is one of the professional suppliers of distribution switchgear and control equipment in China. Founded in 2013, the company is rooted in Yueqing, Wenzhou — the Capital of Electrical Appliances in China. It owns independent brands such as "OFA", and its products cover multiple industries and applications including power, energy, industrial automation, construction, and equipment manufacturing.
Rooted in Yueqing for over a decade, OFA has been providing global partners with low voltage and high voltage distribution switchgear, control equipment, and supporting protection accessories featuring high stability and cost advantages. Upholding honest and law-abiding operations, OFA has been rated as tax credit grade A for seven consecutive years, earning long-term trust from EPC contractors, OEMs, and distributors worldwide.
From low-voltage miniature isolation to heavy industrial molded case protection, OFA engineers system-wide reliability.
Primary function is to make, carry, and break currents under normal circuit conditions, and to break currents under specified abnormal conditions such as overloads and short circuits.
At the end of modern power distribution systems, the safety and stability of every branch circuit relies on a sophisticated guardian unit.
Intelligent Air Circuit Breaker product line designed as a high-performance core protection and power control device for central switchboards.
Specialized, high-reliability protection solution designed for earth leakage fault detection and prevention of electric shock hazards.
Innovatively integrates three core functions — overload protection, short-circuit protection, and high-sensitivity earth leakage detection into a single enclosure.
Integrates robust mechanical isolation with high-current withstand capability, providing visual safety break points for maintenance personnel.
Tailored component configurations optimized for high-demand commercial, renewable, and heavy industrial environments.
In 1000V DC and 1500V DC solar array fields, OFA high-voltage DC circuit breakers protect PV strings against reverse current backfeed caused by shading or localized short circuits. Designed for high ambient temperature resilience up to +70°C inside outdoor IP65 enclosures.
Containerized lithium-ion BESS architectures demand ultrafast isolation of DC battery racks during thermal runaway or busbar short faults. OFA high-voltage DC breakers feature low internal resistance to prevent energy loss and high short-circuit interrupting ratings up to 50kA DC.
DC fast-charging infrastructure operates at voltages ranging from 400V DC to 1000V DC. OFA breakers provide dual-stage backup protection between grid-side rectifiers and vehicle charging connectors, ensuring quick disconnection under overload conditions.
Modern green data centers are migrating from AC UPS to 380V DC power architectures to reduce conversion losses by up to 10%. OFA OEM DC breakers deliver high-density DIN-rail and chassis mounting options tailored for server rack distribution units (PDUs).
Integrating heavy industrial machinery, localized solar power, and emergency backup generators into sub-distribution panels requires coordinated protection curves to ensure selective tripping and zero downtime for non-faulted circuits.
DC traction power networks operating at 750V DC / 1500V DC utilize OFA high-capacity circuit breaking components to isolate auxiliary power circuits and signaling equipment from transient voltage surges and track fault conditions.
Rigorous engineering metrics designed to assist specifying electrical engineers and OEM procurement teams.
| Series Model | Protection Tech | Rated Voltage (Ue) | Rated Current (In) | Ultimate Breaking (Icu) | Compliance Standards |
|---|---|---|---|---|---|
| OFA HV-DC Series | Thermal-Magnetic / Dynamic Arc Chute | Up to 1500V DC | 1A – 63A (Modular) | 10kA – 20kA | IEC 60947-2, UL 489B |
| OFM1 Series MCCB | Molded Case Electronic & Thermal | 400V / 690V AC, 250V DC | 16A – 1250A | 35kA – 100kA | IEC/EN 60947-2, CE, CCC |
| OFD4Z7 / OFP MCB | Miniature Magnetic Interruption | 230V / 400V AC, 125V DC | 1A – 63A | 6kA – 10kA | IEC 60898-1, CE |
| NB1L / OFPM RCBO | Residual Current + Overcurrent | 240V / 415V AC | 6A – 40A (30mA Sensitivity) | 6kA – 10kA | IEC/EN 61009-1 |
| OFW1 Series ACB | Intelligent Intelligent Air Break | 400V / 690V AC | 630A – 6300A | 85kA – 120kA | IEC 60947-2, ISO9001 |
How OFA R&D is pushing the boundary of solid-state switching, hybrid fault isolation, and AI-driven telemetry.
Implementation of high-coercivity Neodymium (NdFeB) magnetic blowout inserts within standard DIN-rail profiles to reduce arcing time under 1500V DC to under 5ms.
Integrating fast mechanical actuators with parallel SiC MOSFET commutators to achieve zero-arc interruption and ultra-low conduction losses for BESS power racks.
Embedding real-time current, voltage, contact degradation, and temperature sensors inside breaker bodies, communicating via wireless Modbus/Zigbee to cloud SCADA.
Transitioning to full Solid-State Circuit Breaker (SSCB) architectures featuring sub-microsecond fault interruption (<10μs) for next-generation DC microgrids and aerospace power systems.
Full-chain collaborative support from initial technical alignment to mass production and international compliance certification.
Submit your system operating parameters (DC voltage, breaking capacity, tripping curves, enclosure dimensions, and ambient constraints). Our senior application engineers evaluate short-circuit parameters and recommend precise arc chamber geometry.
OFA produces 3D printed samples and short-run production units within 14 working days. Full type-testing is performed in-house, verifying mechanical operation life, temperature rise at rated current, dielectric withstand, and DC short-circuit breaking performance.
Upon client sign-off, automated assembly lines execute production under 100% full-inspection SOPs. Custom private labeling, laser-etched wiring diagrams, custom packaging, and serial tracking codes are applied seamlessly prior to global shipping.
Get immediate expert answers regarding DC protection selection, OEM customizations, and compliance standards.
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