Explore our flagship high-performance RCBOs, MCBs, RCCBs, and MCCBs built for precise earth leakage and overcurrent mitigation.
In modern commercial, residential, and industrial low-voltage electrical distribution networks, single-phase and three-phase circuits require comprehensive defense mechanisms against current overloads, short-circuit faults, and subtle insulation degradation leading to earth leakage currents. The OFC Series Residual Current Operated Circuit Breaker with Overcurrent Protection (RCBO) engineered by Wenzhou OFA Electrical Technology Co., Ltd. represents a state-of-the-art technological convergence. By integrating the functionality of a Miniature Circuit Breaker (MCB) and a Residual Current Circuit Breaker (RCCB) into a single compact DIN-rail module, the OFC Series delivers all-in-one safety without compromising panel space.
Combines thermal-magnetic overcurrent trip units (B, C, D curves) with ultra-precise Zero-Sequence Current Transformers (ZSCT) for instantaneous earth leakage shutdown (< 0.1s).
Unlike legacy "MCB + RCD" side-by-side modular assemblies, the OFC Series utilizes a streamlined 1P+N or 2P footprint (18mm to 36mm width), freeing up 50% cabinet space.
Engineered with silver-alloy contacts and arc-extinguishing chute grids, delivering reliable short-circuit breaking capacities of 6kA and 10kA under IEC/EN 61009-1 standards.
| Technical Parameter | OFC Series RCBO (OFA Standard) | Traditional MCB + Add-on RCD Module | Basic Standalone RCCB |
|---|---|---|---|
| IEC Standard Compliance | IEC/EN 61009-1, CE Certified | IEC 60898-1 + IEC 61008-1 | IEC/EN 61008-1 |
| Protection Coverage | Overload + Short-Circuit + Earth Leakage | Overload + Short-Circuit + Earth Leakage | Earth Leakage Only (Requires External Fuse/MCB) |
| Modular Width (1P+N) | 18mm - 27mm Compact | 36mm - 54mm Bulky | 36mm |
| Residual Current Type | Type A (AC & Pulsating DC), Type AC | Primarily Type AC | Type AC or Type A |
| Rated Breaking Capacity (Icn) | 6,000A / 10,000A | 4,500A / 6,000A | N/A (Short Circuit Rating Dependent) |
| Tripping Response Time | ≤ 0.04s at 5 IΔn | ≤ 0.1s | ≤ 0.1s |
Wenzhou OFA Electrical Technology Co., Ltd. is strategically based in Yueqing, Wenzhou—universally recognized as the "Capital of Electrical Appliances in China." Founded in 2013, OFA leverages over a decade of concentrated industrial development, complete raw material supply chains, and advanced precision engineering to supply global markets with cost-effective, high-tier switchgear components.
Automated winding, contact riveting, and high-speed housing sonic welding ensure high repeatability and tight magnetic tolerance across millions of units produced annually.
Every single OFC Series RCBO undergoes rigorous automatic calibration for thermal trip curves, instant magnetic trip limits, and micro-amp residual current sensitivities.
Direct access to local high-purity copper smelting, silver-tin-oxide contact tip manufacturing, and flame-retardant VO grade polycarbonate molding lowers BOM cost.
Custom laser etching, tailored current ratings (6A to 63A), non-standard tripping curves, and private label branding to serve global distributors and panel builders.
Rooted in Yueqing for over a decade, Wenzhou OFA Electrical Technology Co., Ltd. adheres strictly to ISO9001 Quality Management System principles. Recognized with a Tax Credit Grade A rating for seven consecutive years, we never compromise on copper coil purity, contact thickness, or plastic casing fire-retardancy.
The electrification of heating, transport, and renewable generation is rapidly changing low-voltage power networks. Circuit protection technology is evolving from passive mechanical separation to active, intelligent, and highly sensitive residual current detection.
Modern electronics (variable speed drives, solar inverters, EV chargers) inject smooth DC components into leakage currents. Standard Type AC residual devices fail to trip. Demand for Type A and Type B RCBOs is growing at over 15% CAGR globally.
Smart infrastructure requires real-time monitoring of insulation degradation. Next-gen OFC Series devices are incorporating digital communication ports (RS485 Modbus, wireless IoT) to signal early earth leakage warnings before catastrophic tripping occurs.
Environmental standards (RoHS, REACH, LEED) demand zero hazardous materials in arc chutes and casing plastics. OFA manufactures using 100% recyclable, halogen-free, self-extinguishing thermosetting polymers.
From residential consumer units to heavy industrial automation lines and renewable microgrids, OFA's circuit protection components are engineered for challenging environments.
Inverter AC output circuits require Type A or Type B RCBOs to handle smooth DC residual components. OFC Series guarantees non-tripping under high frequency harmonic noise while offering rapid safety isolation during actual earth faults.
Commercial and residential EV chargers require high-sensitivity protection (≤30mA) against direct current earth leakage. OFC RCBOs protect charge points from nuisance trips while safeguarding human lives from touch potential hazards.
Hyperscale data servers generate continuous capacitive leakage currents. OFA's selective and time-delayed RCBOs prevent cascade tripping across sub-distribution panels, maintaining high power availability.
High ambient temperature resistance and robust vibration immunity make OFC Series ideal for installation in outdoor air-conditioning distribution units and commercial building panels.
International EPC contractors, wholesalers, and panel builders demand robust compliance, predictable lead times, and seamless logistics. Wenzhou OFA Electrical Technology Co., Ltd. satisfies global procurement criteria through complete end-to-end service support.
Our products are engineered and tested in strict accordance with international frameworks including IEC/EN 61009-1, IEC 60947-2, CE, and RoHS directives. Full type test reports are available for engineering audit review.
From custom rating dials and private label artwork to export-grade seaworthy/airworthy packaging, OFA provides flexible minimum order quantities (MOQs) and standard 15 to 25-day delivery turnarounds.
Founded in 2013, Wenzhou OFA Electrical Technology Co., Ltd. is one of China's premier professional suppliers of low-voltage distribution switchgear and industrial control equipment. Operating out of Yueqing—the heart of China's electrical machinery cluster—OFA develops independent brands such as "OFA" while serving global OEMs across power, solar energy, industrial automation, and construction sectors.
OFA emphasizes practical product reliability over empty conceptual claims. Our technical laboratory is equipped with full-process type testing devices, capable of executing rigorous verifications for mechanical operating life, temperature rise limits, insulation resistance, and impulse withstand voltage.
"We adhere to honest, law-abiding operations and have been rated as a tax credit grade A enterprise for seven consecutive years, earning long-term trust across European, South American, Asian, and Middle Eastern markets."
In addition to the OFC Series RCBO, OFA manufactures a full spectrum of high-reliability distribution control gear:
Includes BA88, DCM1, DCOF1, and OFM1 series designed to make, carry, and break currents up to 800A under heavy overload and short-circuit faults.
OF6KA, OF10KA C65, OFKL, OFL7, and OFP series offering space-saving DIN-rail protection for terminal branch circuits across residential and commercial boards.
OFW1 Intelligent Universal Circuit Breaker line precisely engineered as high-current main switch protectors with deep digital intelligence and communication.
OFDX, OFPM, OFID, and OFAP6 series delivering graded, high-sensitivity earth leakage current protection without integral overcurrent release.
OFC Series, NB1L, and OFMIN series integrating earth leakage, overload, and short-circuit protection into a single modular enclosure.
OFIS-125A and OFIS-BH series main isolating switches providing reliable circuit disconnect functionality under load conditions.
See why engineering leads, EPC integrators, and facility managers rely on OFA products for critical infrastructure.
"As a system integrator, our company has collaborated with OFA on several industrial automation projects in Central Europe. Their product line is remarkably consistent, simplifying our procurement and cabinet integration. The zero defect out-of-box rate drastically reduced our commissioning time."
"We purchased OFA's intelligent power monitoring components and OFC Series RCBOs to retrofit distribution boards in our manufacturing workshop. Installation on standard DIN rails was smooth. They have operated flawlessly for over a year, preventing false trips while protecting sensitive machinery."
"Deploying OFA's earth leakage components across commercial real estate properties in Bangkok has been a great operational decision. Their responsive support team provided clear technical documentation and rapid factory lead times for our custom labeling."
"Our solar PV projects required highly stable residual current protection capable of operating under high ambient heat and DC ripple components. OFA's Type A RCBOs met all core engineering criteria at a very competitive factory direct cost."
Clear, engineering-backed answers regarding OFC Series RCBO products, customization, compliance, and supply logistics.
A standard MCB (Miniature Circuit Breaker) protects electrical circuits solely against overcurrent conditions—specifically thermal overloads and high-current short circuits. An RCBO (Residual Current Operated Circuit Breaker with Overcurrent Protection), such as the OFC Series, combines thermal-magnetic overcurrent protection with high-sensitivity residual current (earth leakage) protection in one module. It safeguards both equipment from electrical fires and humans from direct contact electrical shocks.
Using an integrated OFC Series RCBO offers three key engineering advantages: First, it saves up to 50% cabinet space on DIN rails. Second, in the event of an earth fault on a specific branch circuit, only the affected branch RCBO trips, leaving remaining sub-circuits operational (preventing total panel blackouts). Third, it simplifies installation wiring and reduces potential loose terminal connections inside the distribution board.
For personal human shock protection in residential dwellings, bathrooms, and outdoor socket circuits, 30mA (0.03A) instantaneous tripping is the global standard requirement under IEC 60364. For dedicated equipment protection or anti-fire mitigation in commercial/industrial buildings, 100mA or 300mA selective/time-delayed sensitivity options are available upon request.
Yes. While standard Type AC RCBOs detect sinusoidal AC residual currents, OFA offers Type A OFC Series units designed to detect both sinusoidal AC and pulsating DC residual currents typical in modern circuits containing power electronics, LED drivers, solar inverters, and domestic appliances.
OFA provides comprehensive custom manufacturing services including custom laser etching of client logos, specialized rated current branding (6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A), custom trip curve characteristics (B, C, D curves), color-coded toggle handles, and private-label master carton packaging.
Standard stock items ship within 3 to 7 working days. For OEM/ODM bulk production runs, the standard manufacturing lead time is 15 to 25 calendar days. Flexible MOQ policies apply based on component customization requirements.
OFA maintains ISO9001 certified quality management systems. Every single production batch undergoes 100% full-inspection SOPs: high-potential voltage withstand testing, thermal trip calibration, magnetic trip verifications, and residual tripping response time checks prior to export packing.
Discover our extended line of RCCBs, MCBs, MCCBs, and specialized DC protection components engineered for reliable grid integration.
OFA Electrical
