Rigorous full-process type testing ensures maximum short-circuit interrupting capacity and long-term operational stability.
Wenzhou OFA Electrical Technology Co., Ltd. is a premier Chinese manufacturer specialized in low-voltage distribution switchgear, digital control equipment, and specialized electrical circuit protection solutions.
Founded in 2013, Wenzhou OFA Electrical Technology Co., Ltd. (OFA Electech) is deeply rooted in Yueqing, Wenzhou — widely recognized as the Capital of Electrical Appliances in China. Operating across independent brand portfolios including "OFA", our production facility combines direct access to raw material supply chains with advanced automated assembly, delivering circuit breaker technologies that achieve optimal cost-performance equilibrium without compromising technical precision.
The global shift toward decentralized power generation, solar photovoltaic (PV) integration, Battery Energy Storage Systems (BESS), and Electric Vehicle Charging Infrastructure (EVCI) demands resilient protection devices. Our Circuit Breaker At AF solution series is tailored to handle non-linear industrial loads, severe transient overvoltages, and high short-circuit fault currents across modern commercial and utility grids.
Strictly adhering to ISO9001 Quality Management System specifications, OFA Electech enforces rigorous 100% full-inspection Standard Operating Procedures (SOPs). Every unit undergo comprehensive verification including mechanical endurance, contact resistance, calibration of thermal-magnetic trip units, dielectric insulation testing, and temperature rise limits under max rated currents prior to dispatch.
From sub-distribution sub-circuits to heavy industrial main incoming switchboards, explore our complete line of protection switchgear manufactured under international IEC 60898-1 and IEC 60947-2 standards.
| Category | Key Series | Rated Current (In) | Breaking Capacity (Icu) | Primary Standards | Core Industrial Application |
|---|---|---|---|---|---|
| Miniature Circuit Breakers (MCB) | OFL7, OFL8, OFAFT, OFDZ47, OFDL, OFEU, OFP, OF10KA, OFKL-NXB | 1A – 125A | 4.5kA / 6kA / 10kA | IEC/EN 60898-1, CE | Residential distribution panels, commercial branch circuits, HVAC units. |
| Molded Case Circuit Breakers (MCCB) | BA88, OFM1, DCM1, DCOF1, OFBLT, OF1, OFA-M1 | 16A – 1600A | 25kA – 100kA | IEC/EN 60947-2, UL 489 | Industrial switchboards, motor control centers, PV combiner boxes. |
| Residual Current Breakers (RCCB / RCBO) | OFGX, OFAP6-AC, OFKL-80A, OFDPN, OFDX, OFID, NB1L, OFC | 6A – 100A | Sensitivity: 30mA, 100mA, 300mA | IEC/EN 61008-1, IEC 61009-1 | Earth fault safety, personnel protection, wet area installations. |
| Air Circuit Breakers (ACB) | OFW1 Intelligent Universal Series | 630A – 6300A | 85kA – 120kA | IEC/EN 60947-2 | Main low-voltage power intake, data centers, heavy manufacturing. |
| Isolating Switches (IS) | OFIS-125A, OFIS-BH, OFIS-DS | 32A – 125A | Category AC-22A / AC-23A | IEC/EN 60947-3 | Safety isolation, industrial machinery disconnects, solar arrays. |
OFA's MCB series (including the heavy-duty OF10KA and compact OFL7/OFL8) protect low-voltage electrical lines against thermal overload and electromagnetic short-circuits. Designed with flame-retardant thermohardening housings, dynamic arc-extinction chutes, and silver-alloy contact points, our MCBs guarantee fast tripping response (<10ms) under catastrophic fault conditions, preserving cable integrity and downstream equipment.
For high-capacity power feeder distribution, OFA provides state-of-the-art MCCBs such as the BA88-250E and OFM1/630A series. Featuring adjustable thermal-magnetic or microprocessor-based electronic trip units (LSI protection curves), our MCCBs deliver precision selective coordination, preventing nuisance tripping across complex industrial networks while providing up to 100kA breaking capacity.
Preventing direct electrical shock and insulation leakage fires requires sensitive earth leakage protection. OFA's OFGX, OFAP6-AC (Waterproof), and OFKL-80A series integrate zero-sequence current transformers to detect ground faults as low as 30mA. The combined RCBO models house earth leakage, overload, and short-circuit protection within a compact single-module DIN-rail width.
Our Circuit Breaker At AF equipment is engineered to withstand tough ambient conditions, high humidity, variable temperatures, and electrical noise.
Installed in primary sub-distribution boards to secure lighting, elevators, HVAC units, and IT server circuits with low heat dissipation and zero maintenance requirements.
DC-rated MCBs and high-voltage MCCBs tailored for solar combiner boxes, string inverters, and battery bank isolation, stopping reverse currents and arc surges.
Motor-circuit protection MCCBs providing D-curve or K-curve trip characteristics capable of enduring high inrush current spikes without nuisance tripping.
Specialized Type A / Type B RCCBs and high-performance RCBOs engineered to detect smooth DC ground fault leakage currents generated by EV onboard chargers.
From custom laser marking and custom trip curves to private-label packaging and bespoke terminal configurations, OFA Electech delivers flexible end-to-end manufacturing support.
Engineering alignment on breaking capacity, voltage ratings, mechanical life, and regional grid code certifications.
3D modeling, thermal simulation, rapid prototyping, and type-testing under extreme load conditions in our lab.
Robotic assembly, digital inspection stations, 100% full-inspection calibration for trip sensitivity and timing.
Reinforced sea/air export packaging, customs compliance paperwork, and full lifecycle engineering technical support.
Leading the transition from traditional passive protection to active diagnostic intelligent electrical architectures.
Integrating RS485 Modbus, Modbus-TCP, and wireless communication protocols (Zigbee/LoRa) into smart MCBs and MCCBs. Real-time telemetry monitoring for current, voltage, active power, temperature, and residual current allows facility managers to execute predictive maintenance prior to fault occurrence.
Developing next-generation Solid-State Protection units utilizing Wide-Bandgap (SiC / GaN) power semiconductors. SSCBs offer microsecond-level fault isolation (<10 microseconds), zero mechanical arc flash, and extended mechanical endurance for sensitive microgrids and DC distribution hubs.
Pioneering halogen-free, non-toxic thermoplastic materials for circuit breaker housings, compliant with EU RoHS and REACH regulations. Our manufacturing process minimizes carbon footprints while enhancing thermal dissipation and arc resistance efficiency.
Answers to common engineering, selection, compliance, and ordering queries for industrial electrical buyers.
MCBs (Miniature Circuit Breakers) protect sub-circuits up to 125A against overloads and short circuits. MCCBs (Molded Case Circuit Breakers) handle higher currents (up to 1600A) with adjustable trip settings and higher breaking capacities (up to 100kA). RCCBs (Residual Current Circuit Breakers) detect earth leakage currents to prevent electric shock and fires but do not protect against overloads. RCBOs combine both MCB (overload/short-circuit) and RCCB (earth fault leakage) functions into a single unified housing.
B Curve (3-5 In): Ideal for resistive loads with low inrush currents, such as domestic lighting and heating circuits. C Curve (5-10 In): Designed for standard commercial loads, general inductive equipment, and fluorescent lighting. D Curve (10-20 In): Specifically engineered for high inrush inductive loads, including industrial motors, transformers, and power supplies, preventing false tripping during startup power surges.
Icu (Ultimate Short-Circuit Breaking Capacity) is the maximum short-circuit current the breaker can interrupt without being destroyed, though it may require inspection or replacement afterward. Ics (Service Breaking Capacity) is the current level the breaker can interrupt repeatedly and remain fully operational without loss of performance (expressed as a percentage of Icu, e.g., 75% or 100% Ics=Icu).
Standard thermal-magnetic trip units are calibrated at a reference ambient temperature of 30°C or 40°C according to IEC standards. When operated in higher ambient temperatures (e.g., inside sealed outdoor solar enclosures reaching 55°C+), the thermal bimetal strip expands earlier. A derating factor (typically 0.85 – 0.92) must be applied to the nominal current rating (In) to avoid nuisance tripping.
Yes. OFA products comply with key international standards including IEC/EN 60898-1, IEC/EN 60947-2, IEC 61008, IEC 61009, CE mark directives, CCC certification, and ISO9001 quality management guidelines. Detailed test reports and certificates are available upon request for engineering submittals.
Absolute agreement. OFA specializes in OEM/ODM collaboration. We offer custom branding, private-label laser marking, custom tripping curves, specialized voltage/frequency ratings (e.g., 60Hz or DC applications), customized packaging, and tailor-made terminal connections for global switchgear builders.
Type AC: Detects sinusoidal AC residual currents. Type A: Detects sinusoidal AC and pulsating DC ground fault currents. Type F: Detects composite frequency residual currents from single-phase variable speed drives. Type B: Detects smooth DC residual currents, essential for 3-phase EV chargers, solar inverters, and medical equipment.
For standard stocked products, dispatch can occur within 5-7 business days. For customized OEM/ODM batch orders, lead times range between 20 to 30 days depending on order volume. We maintain flexible Minimum Order Quantity (MOQ) policies to support growing distributors and specialized EPC contractors.
OFA combines over a decade of dedicated low-voltage switchgear expertise, localized supply chain cost advantages in Yueqing, rigorous 100% factory full-inspection standards, Tax Credit Grade A reliability for 7 consecutive years, and direct engineering-to-engineering technical support throughout project lifecycles.
You can reach out directly via our official product links, contact forms, or email. Our team of experienced electrical application engineers will review your electrical single-line diagrams (SLD) or product specifications to provide detailed technical proposals and competitive pricing within 24 hours.
Complete protection coverage engineered for commercial panels, smart homes, solar arrays, and high-load industrial sub-stations.
OFA Electrical
