TOB1Z-63 2P 1000V DC MCB
Optimized for 1000V DC solar PV string combiner boxes. Features calibrated thermal-magnetic trip units, 6kA/10kA breaking capacity, C curve protection, and high-dielectric polycarbonate housing.
Datasheet & Details
Direct Engineering Insight · Global Sourcing Guide
How to Select, Size, and Procure DC Miniature Circuit Breakers (DC MCB) for Solar PV, BESS & DC Microgrids
As utility-scale photovoltaic arrays, commercial Battery Energy Storage Systems (BESS), electric vehicle fast-charging hubs, and decentralized DC microgrids proliferate worldwide, electrical engineers and international procurement officers face critical safety and operational questions. Direct current presents severe arcing challenges because DC current has no natural zero-voltage crossing, meaning an electrical arc does not extinguish on its own as it does in alternating current networks.
Zhejiang TMB Electric Co., Ltd. delivers engineered, TÜV Rheinland verified DC Miniature Circuit Breakers (DC MCBs) rated from 12V to 1000V DC and 1A to 125A. Designed with permanent magnetic blowout assemblies, multi-plate arc chute deionizers, and premium Silver Tin Oxide (AgSnO2) contacts, our products prevent thermal runaway, eliminate catastrophic contact welding, and guarantee dependable fault isolation under extreme load regimes.
- Specialized magnetic blowout arc extinction chambers engineered specifically for zero-crossing-free DC fault currents up to 10kA.
- Full compliance with international standards IEC/EN 60947-2 (industrial/PV) and IEC/EN 60898-2 (infrastructure).
- Factory direct supply from Liushi, Wenzhou: low MOQ from 5 units, private OEM/ODM labeling, and fully traceable component metallurgy.
0+Years in Low-Voltage Protection
0 m²Verified Workshop Area
0VMax DC Operating Voltage
0 kAPeak Breaking Capacity (Icu)
0 pcsFlexible Trial Order MOQ
Product Selection & Recommendations
Engineered DC Miniature Circuit Breakers for Severe Duty Demands
Discover our best-performing DIN-rail DC protection models designed for solar photovoltaic strings, battery storage energy management, and telecom equipment rooms.
TOB1Z-125 High-Current DC MCB
Engineered for lithium-ion battery banks, hybrid off-grid inverters, and EV DC sub-circuits. Delivers continuous current carrying from 80A to 125A at 600V DC with reinforced arc-splitting plates.
Datasheet & Details
TOB1Z-63 500V DC MCB (B & C Curve)
Tailored for telecom 48V/96V rectifiers and mid-voltage solar arrays. Available with fast-acting B curve (3–5 In) and standard C curve (7–10 In) to protect sensitive semiconductor electronic loads.
Datasheet & Details
TOM7Z 1000V DC MCCB Series
Heavy-duty molded case breaker rated from 100A to 250A at 1000V DC. Serves as master circuit disconnect and overload trip device for central inverter inputs and high-capacity battery racks.
Datasheet & Details Engineering Comparison Matrix
Technical Specifications: DC MCB Sizing & Rating Reference
Compare rated current, pole configurations, system voltage, and breaking capacities across our standard DIN rail production models.
| Series Model | Pole Number | Rated Voltage (Ue) | Rated Current (In) | Breaking Capacity (Icu/Ics) | Tripping Curve | Standard Compliance | Primary Application |
|---|---|---|---|---|---|---|---|
| TOB1Z-63 1P | 1 Pole | 250V DC | 1A, 3A, 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A | 6 kA / 6 kA | B (3-5 In) / C (7-10 In) | IEC 60947-2, IEC 60898-2, CE | Telecom power supply, DC auxiliary control circuits |
| TOB1Z-63 2P | 2 Poles | 500V / 600V / 1000V DC | 3A, 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A | 6 kA / 10 kA | C Curve (7-10 In) | IEC 60947-2, CE, RoHS | Residential rooftop solar strings, 600V PV combiner boxes |
| TOB1Z-63 4P | 4 Poles (Series) | 1000V / 1200V DC | 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A | 10 kA / 7.5 kA | C / D Curve | IEC 60947-2, CE | High-voltage commercial PV arrays, ground-mount solar arrays |
| TOB1Z-125 | 1P, 2P | 250V / 500V / 600V DC | 80A, 100A, 125A | 10 kA / 10 kA | C Curve (7-10 In) | IEC 60947-2, CE | Low-voltage lithium battery banks (48V/51.2V), DC inverter mains |
| TOM7Z (DC MCCB) | 2P | 1000V DC | 100A, 125A, 160A, 200A, 250A | 20 kA / 15 kA | Thermal-magnetic fixed | IEC 60947-2, CE | Central battery ESS containers, multi-string commercial combiner hubs |
*All breakers undergo 100% full-current thermal calibration and dielectric withstand testing before leaving Zhejiang TMB Electric Co., Ltd. custom factories.
Get a Quote Market Dynamics & Insights
Future Procurement Trends in DC Miniature Circuit Breakers (2025–2030)
How global energy transitions, evolving technical standards, and supply chain shifts are reshaping international purchasing decisions for DC switchgear.
1. Transition toward Higher DC Voltages (1000V & 1500V DC)
To minimize I²R transmission power losses and reduce cable cross-sectional copper weights, photovoltaic and BESS architectures are rapidly shifting from 600V toward 1000V and 1500V DC. Sourcing demands have correspondingly elevated the standard requirement from simple 1-pole/2-pole devices to multi-pole series breakers and compact 1000V DC MCBs engineered to suppress longer, hotter plasma arcs without ballooning enclosure footprint dimensions.
2. Surge in Demand for Non-Polarized (Bi-Directional) Breakers
Battery Energy Storage Systems inevitably require bidirectional current: power flows inward during battery charging and outward during discharging. Traditional polarized DC MCBs, which rely on a unidirectional magnetic blowout field, fail catastrophically if current reverses. Procurement managers at leading solar EPCs and ESS integrators now insist on non-polarized DC MCBs to eliminate installer wiring error risks and guarantee foolproof operation under bidirectional energy flows.
3. Integration of Smart Auxiliary Contacts & Remote Shunt Trips
Modern industrial DC switchboards and unattended microgrid containers no longer operate as passive protection stations. Sourcing contracts frequently mandate built-in auxiliary micro-switches (OF), fault indicator contacts (SD), shunt trip coils (MX), and under-voltage releases (MN). These enable SCADA monitoring systems, programmable logic controllers, and IoT gateways to detect tripped statuses instantly and execute remote power-down sequences during fire alarm triggers.
4. Direct Procurement from Integrated Industrial Clusters (Liushi Advantage)
Global purchasers are moving away from middle-tier trading brokers, opting instead to establish direct relationships with established factory facilities in Liushi, Wenzhou—China's low-voltage capital. Sourcing directly from verified manufacturers like Zhejiang TMB Electric Co., Ltd. ensures tight component traceability, shorter tooling turnaround for custom current steps, certified lab testing, and significant pricing resilience against raw metal volatility.
R&D and Engineering Trajectories
Technical Evolution: How Modern DC MCB Architecture Is Changing
Behind the exterior plastic shell lies a fierce engineering struggle against electromagnetic heat and plasma degradation. Here is how modern DC breaker technology has evolved.
Magnetic Blowout & Aerodynamic Splitter Plate Optimization
In an AC breaker, the arc naturally dies as voltage drops to zero at every half-cycle (50 or 60 Hz). A DC fault arc, conversely, acts like a continuous plasma flame reaching temperatures above 5,000 K. To overcome this, Zhejiang TMB Electric Co., Ltd. incorporates permanent neodymium rare-earth magnets positioned beside the primary arcing contacts. When the contacts separate, the magnetic field exerts an intense Lorentz force ($F = I \times B$) that accelerates the electric arc away from the precious metal contacts directly into a 13-plate deionizing arc chute.
Inside the chute, the extended arc is split into a series of short micro-arcs, multiplying the overall arc voltage until it surpasses the system’s open-circuit source voltage, effectively collapsing the current in under 10 milliseconds.
Silver Tin Oxide ($AgSnO_2$) vs. Traditional Contact Metallurgy
DC breaking cycles cause asymmetrical electrical erosion and material transfer from anode to cathode. While older designs utilized Silver Cadmium Oxide ($AgCdO$), modern environmental mandates (RoHS/REACH) and endurance testing favor Silver Tin Oxide ($AgSnO_2$). Our contacts provide exceptional resistance against contact welding during high-inrush capacitor bank charging, reduce contact resistance below 0.5 milliohms, and guarantee stable trip thresholds over thousands of mechanical operations.
Dielectric Shell & Thermal Stability
Breaker housings are molded from reinforced, halogen-free, glow-wire tested PA66 nylon rated UL94 V-0 for flammability. Even under extreme internal arc-fault plasma release, the exterior enclosure maintains structural rigidity, prevents flame blowouts into neighboring DIN rail components, and exhibits exceptional tracking resistance (CTI > 600V).
Enterprise Strengths
Why Top Global Energy Brands Partner with Zhejiang TMB Electric Co., Ltd.
Headquartered in Huabei Village, Liushi Town, Wenzhou—China’s epicenter for low-voltage electrical switchgear—Zhejiang TMB Electric Co., Ltd. combines 24 years of manufacturing heritage with modern lean fabrication practices. Over two decades of specialized focus in circuit breaker mechanics enables us to deliver unmatched reliability, technical precision, and commercial flexibility to buyers in more than 100 countries.
TÜV Rheinland Verified Factory
Our 5,700 m² production base and 92-member specialized workforce have undergone on-site verification by TÜV Rheinland.
Comprehensive Supply Ecosystem
Located in Liushi, we source high-precision silver contacts, copper bimetals, and flame-retardant housings within minutes.
Flexible OEM / ODM Customization
Custom trip curve calibration (B, C, D), brand laser etching, special voltage steps, and tailored multi-pole DIN assemblies.
Low Trial MOQ (From 5 Pcs)
Order trial batches starting from 5 pieces to verify physical samples, thermal response curves, and lab tests before mass rollout.
24 YearsIndustry Heritage
Zero-Defect Quality Control
Rigorous Manufacturing & Testing Protocol for DC MCBs
DC applications demand uncompromising safety. Every batch of miniature circuit breakers produced at Zhejiang TMB Electric Co., Ltd. passes through 6 mandatory inspection gates before shipment packaging.
1. Raw Material Audit
Spectrographic verification of bimetal thermal sheets, pure copper terminal lugs, and silver alloy contact rivets.
2. Mechanism Assembly
Precision calibration of internal spring release latches and permanent magnetic arc blowout positioning.
3. Instantaneous Magnetic Test
High-current pulse testing to verify instant magnetic tripping points within prescribed curve boundaries (B/C/D).
4. Thermal Overload Calibration
Prolonged 1.05 In and 1.30 In current immersion tests inside temperature-stabilized calibration baths.
5. Dielectric High-Voltage Test
2,500V AC dielectric breakdown check across open contacts and between pole housings to ensure zero leakage.
6. Mechanical Endurance Run
Automated pneumatic toggling verifies smooth switch action for up to 20,000 mechanical operations.
Frequently Asked Questions
DC Miniature Circuit Breaker: Sourcing & Engineering FAQ
Clear, definitive answers to the most common technical questions posed by global procurement managers, solar installers, and system integrators.
Why can an AC circuit breaker never substitute for a genuine DC Miniature Circuit Breaker?
Alternating current alternates polarity 100 or 120 times every second (50Hz / 60Hz), creating periodic zero-voltage crossings that naturally collapse electrical arcs. Direct current possesses continuous, unidirectional voltage without natural zero-crossings. An AC MCB tripped under high DC voltage will experience an uninterrupted, sustain-burning plasma arc that melts internal contacts, incinerates terminal blocks, and poses severe fire hazards. Dedicated DC MCBs incorporate high-energy neodymium permanent blowout magnets and elongated deionizing splitter chutes to stretch, cool, and extinguish non-zero-crossing DC arcs.
What is the functional difference between polarized and non-polarized DC MCBs?
Polarized DC MCBs utilize a fixed permanent magnetic field designed to push the arc toward splitter plates strictly when current enters through a designated positive terminal (+). If reverse current flows—such as during battery charging/discharging transitions or ground faults—the Lorentz force drives the arc backward into the operating mechanism, triggering catastrophic explosion. Non-polarized DC MCBs utilize symmetric dual-direction magnetic quenching systems or bidirectional arc chutes, safely clearing overcurrent regardless of flow direction.
How do solar engineering contractors correctly size DC MCBs for photovoltaic strings?
Per international standards IEC 62548 and NEC Article 690, DC MCB sizing requires three mandatory checks: 1) Voltage rating (Ue) must exceed string open-circuit voltage at the site's record lowest temperature: Ue ≥ Voc_string × [1 + (Tmin - 25) × αVoc]. 2) Continuous current rating (In) must equal at least 1.25 times the string short-circuit current (Isc), often paired with an additional 1.25 continuous-duty safety factor (1.56 × Isc). 3) Derating coefficients must be calculated based on the maximum ambient operating temperature inside the IP65 combiner box.
What are the critical distinctions between IEC 60898-2 and IEC 60947-2 standards for DC MCBs?
IEC 60898-2 specifies requirements for circuit breakers intended for household, domestic, and similar infrastructure installations operated by uninstructed persons, capping rated DC voltage at 440V DC and rated current at 125A. IEC 60947-2 governs low-voltage switchgear for industrial, commercial, and utility installations operated by trained professionals. It covers voltages up to 1000V or 1500V DC and requires rigorous short-circuit breaking capacity testing under higher DC time constants (L/R ratios up to 15ms).
Why is contact material selection critical in DC Miniature Circuit Breakers for BESS?
Battery Energy Storage Systems have negligible loop impedance, creating prospective short-circuit discharge currents with near-instantaneous rise times. Traditional copper or silver contacts easily weld under DC inrush currents. Zhejiang TMB Electric Co., Ltd. incorporates premium Silver Tin Oxide (AgSnO2) contacts, providing superior anti-welding characteristics, minimal material migration under continuous DC arcing, and higher thermal stability compared to conventional Silver Cadmium Oxide (AgCdO).
How does high ambient temperature inside outdoor IP65 solar enclosures affect DC MCB performance?
Miniature circuit breakers rely on thermal bimetal strips calibrated at a baseline ambient temperature of 30°C or 40°C. Inside an outdoor sealed combiner box exposed to direct sunlight, internal temperatures frequently hit 55°C to 65°C. At these temperatures, the bimetal strip pre-deflects, causing nuisance tripping below the breaker's nominal ampacity. Engineering teams must apply temperature derating multiplier tables (typically 0.85 to 0.90 at 55°C) and provide DIN rail spacing accessories between adjacent multi-pole breakers to prevent collective thermal accumulation.
Optimize Your DC Circuit Protection Infrastructure
Submit your electrical parameters, single-line diagrams, or OEM requests. Our senior electrical engineering team will deliver a comprehensive proposal with matching models, test certificates, and competitive direct factory pricing within 24 hours.
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