In modern industrial, commercial, and residential electrical distribution systems, the OFKL Series Miniature Circuit Breaker (MCB) serves as the definitive frontline safeguard against thermal overloads, short circuits, and system fault currents. Designed and manufactured in accordance with strict international benchmarks including IEC/EN 60898-1 and IEC/EN 60947-2, the OFKL architecture bridges the critical gap between cost-efficiency, mechanical endurance, and high-breaking capacity.
The OFKL series incorporates a multi-grid arc chute mechanism comprising silver-plated copper alloy de-ion plates. When a fault current strikes, the electromagnetic force rapidly drives the electrical arc into the chute, extinguishing it within milliseconds to prevent contact welding and terminal carbonization.
Engineered with a bi-metallic strip calibrated for precise inverse-time thermal trip characteristics against prolonged overloads, combined with a high-speed magnetic coil mechanism that triggers instantaneous tripping under catastrophic short-circuit conditions (up to 10kA Icu).
Molded from high-impact, fire-resistant polycarbonate (UL94 V-0 grade), the housing exhibits exceptional dielectric strength, thermal stability up to 125°C, and dimensional integrity under heavy vibration and environmental stress.
| Technical Parameter | OFKL 1P / 2P Standard | OFKL 3P / 4P Industrial | OFKL-NXB / High-Frame |
|---|---|---|---|
| Rated Current (In) | 1A, 2A, 3A, 4A, 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A | 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A, 80A, 100A, 125A | Up to 125A Frame Rating |
| Rated Voltage (Ue) | 230V / 240V AC (50/60Hz) | 400V / 415V AC (50/60Hz) | 230V to 440V AC / 250V DC |
| Rated Breaking Capacity (Icn/Icu) | 6,000A (6kA) / 10,000A (10kA) | 6,000A (6kA) / 10,000A (10kA) | Up to 15kA (IEC 60947-2) |
| Tripping Characteristics | B Curve (3-5 In), C Curve (5-10 In) | C Curve (5-10 In), D Curve (10-14 In) | B, C, D Tripping Curves |
| Mechanical / Electrical Life | 20,000 Operations / 10,000 Operations | 20,000 Operations / 8,000 Operations | 20,000 / 10,000 Operations |
| Degree of Protection | IP20 (Terminal Area IP40 in Switchboard) | IP20 (Option for IP65 Waterproof Enclosure) | IP20 Terminals, Touch-Safe Design |
Located in Yueqing, Wenzhou—globally recognized as the epicenter of low-voltage electrical component manufacturing—Wenzhou OFA Electrical Technology Co., Ltd. leverages a concentrated ecosystem of raw material suppliers, high-precision stamping facilities, and testing laboratories. This unique industrial aggregation yields distinct competitive advantages for overseas procurement leaders, EPC contractors, and OEM distributors:
From silver contact rivets and bi-metal strips to precision plastic injection molds, 95% of sub-components are sourced within a 15-kilometer radius of our manufacturing plant. This minimizes logistical friction, reduces lead times, and allows us to buffer against global supply chain volatility.
Our production lines integrate digital inspection stations and automated thermal trip testing equipment. Every single OFKL circuit breaker undergoes 100% full-inspection SOPs for tripping sensitivity, voltage drop, insulation resistance, and dielectric strength prior to packaging.
By combining high-volume standard product runs with modular OEM assembly pathways, OFA delivers enterprise-grade electrical components at a cost structure up to 30-40% lower than traditional European brands, without sacrificing international compliance.
The global low-voltage circuit breaker market is undergoing a structural transition driven by decarbonization, decentralization, and digitalization. As commercial buildings and industrial plants integrate rooftop Solar PV systems, Electric Vehicle (EV) charging infrastructures, and Battery Energy Storage Systems (BESS), the demands placed on miniature circuit breakers (MCB) and residual current devices (RCCB/RCBO) have evolved significantly:
OFKL 1P and 2P MCBs provide reliable, space-saving overcurrent protection in consumer units, main switchboards, and sub-panels for apartments, hotels, and retail complexes.
OFKL 3P and 4P MCBs with C and D tripping curves safeguard heavy inductive loads, including 3-phase electric motors, industrial pumps, HVAC compressors, and CNC machine panels.
Specialized DC rated circuit breakers (OFBLT and OF1-PV series) isolate solar arrays, inverter inputs, and battery banks against high-voltage DC fault currents up to 1000V DC.
Waterproof RCCBs (OFAP6-AC series) and high-sensitivity earth leakage breakers protect public EV charging stations, street lighting networks, and marine distribution boxes from electric shock and water ingress hazards.
Founded in 2013, Wenzhou OFA Electrical Technology Co., Ltd. is rooted in Yueqing, Wenzhou — the Capital of Electrical Appliances in China. The company 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 partners with distribution switchgear and control equipment and supporting products that feature stable performance and cost advantages. We adhere to honest and law-abiding operations, have been rated as tax credit grade A for seven consecutive years, and have earned the long-term trust of numerous global clients. Our factory has passed ISO9001 quality management system certification, maintaining large-scale production capacity to handle high-volume urgent orders seamlessly.
Our technical team continues to delve deep into the R&D and improvement of distribution switchgear and control equipment, equipped with full-process type testing and factory inspection devices for mechanical life, temperature rise, and insulation performance verification.
Through flexible production combining standardization and customization, we precisely match customer specification requirements and provide cost-effective configurations backed by responsive long-term lifecycle support.
Digital inspection stations and automated assembly lines ensure every step from raw parts to finished circuit breakers remains under strict in-process control, steadily outputting zero-defect components.
Step 1: Requirement Analysis & Solution Matching: Review standard frameworks or submit site data for immediate matching with proven circuit protection configurations.
Step 2: Solution Detailing & Simulation: OFA engineers provide system topology diagrams, bill of materials (BOM), and breaker characteristic curves.
Step 3: Agile Delivery & Batch Production: Rapid fulfillment utilizing standardized inventory and high-speed SMT/assembly lines.
Step 4: Acceptance Guidance: Provision of wiring diagrams, installation guidelines, and remote engineering support.
Step 1: In-depth Consultation: Collaborative engineering review analyzing system short-circuit withstand levels, selectivity, and environmental factors.
Step 2: Customized OEM Design: Custom housing colors, laser brand marking, customized tripping characteristics, and specialized packaging.
Step 3: Pre-Shipment Type Testing: Laboratory verification of mechanical endurance, dielectric breakdown, and temperature rise.
Step 4: Full Lifecycle Maintenance: Continuous access to technical documentation, spare parts, and platform telemetry integration.
"As a system integrator, our company has collaborated with OFA on several industrial automation projects. Their product range is quite comprehensive, covering everything from protective relays to communication gateways, which simplifies our procurement and integration work. The product quality is consistent, reducing on-site commissioning hassles."
"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 with our existing system went smoothly. Most importantly, they have been running very 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 energy savings through optimized operational strategies."
"Our PV project required reliable communication management and data acquisition equipment. OFA's products met our core needs at a reasonable price and could adapt to our local outdoor environment. Their engineers provided excellent configuration guidance."
OFA Electrical
