DC MCB (Miniature Circuit Breaker) for Solar, ESS & EV Systems

Safe and reliable DC circuit protection up to 1000V / 125A

  • Wide range: 1P to 4P, up to 1000V / 125A
  • Safe arc extinguishing for DC circuits
  • Ideal para Energía solar fotovoltaica, ESSy EV charging
  • Conforme con IEC 60947-2 / UL standards

KYDB Series Comparison

SeriesCorriente nominalVoltage OptionsAplicacionesNormas
KYDB-63Up to 63A250V / 500V / 750V / 1000VResidential PV, small ESS, DC panels IEC 60947-2, UL 489
KYDB-125Up to 125A250V / 500V / 750V / 1000VC&I solar, EV charging, industrial ESS IEC 60947-2, UL 489
Residential rooftop PV installation with Kuangya DC MCBs

DC MCB Series Selection Guide

When selecting a DC MCB (Miniature Circuit Breaker) for solar PV, ESS, or EV charging projects, the current rating and installation scale are key factors. Kuangya offers two ranges optimized for different needs.

KYDB-63 Series — Designed for up to 63A, it is ideal for residential solar DC circuits y small-scale ESS racks. Compact and reliable, it ensures safe arc extinguishing at up to 1000VDC, making it a cost-effective choice for rooftops up to 10 kW.

KYDB-125 Series — Rated up to 125A, this model supports commercial PV systems, EV charging hubsy industrial ESS containers. With higher breaking capacity, it guarantees compliance with both IEC 60947-2 y UL 489.

Kuangya DC MCBs integrate seamlessly with Fusible CC, DC SPD, DC Switch Disconnectorsy Cajas combinadoras FV, ensuring complete protection coordination.

📌 Consejo: Elija KYDB-63 for residential or small ESS, and KYDB-125 for commercial solar, EV charging, or large-scale ESS. For customized selection, reach out via our Enquiry Form.

All Kuangya DC MCBs are factory-tested under high-voltage DC conditions, ensuring consistent reliability and safety.

What is a DC MCB?

Por qué es importante

A DC MCB (Miniature Circuit Breaker) is essential in modern solar y ESS projects, protecting against overloads and short circuits. Unlike AC breakers, a solar DC MCB is engineered to extinguish persistent DC arcs, ensuring safety in rooftop arrays, battery systems, and EV charging. Compliance with IEC 60947-2 y UL 489 provides global reliability.

🔧 What’s inside

Kuangya DC MCBs feature arc extinguishing chambers, robust silver-alloy contacts, and modular poles from 1P to 4P. Rated up to 1000VDC / 125A, they handle the demands of high-power PV arrays and energy storage systems. Their precision design ensures stable breaking capacity, long service life, and consistent DC circuit protection under harsh operating conditions.

🏠 Where it’s used

DC MCBs are widely applied in residential solar rooftops, commercial PV plants, ESS racksy EV charging hubs. They isolate faults before they damage inverters or batteries, ensuring uninterrupted operation. From small rooftop systems to large industrial ESS containers, Kuangya breakers deliver safe and bankable protection for every scale of project.

🛠️ Install & service

All Kuangya Interruptores de CC are DIN-rail mounted, compact, and designed for easy service. Their modular design allows field replacement without downtime, reducing O&M costs. With clear labeling, quick wiring, and robust housing, these DC distribution breakers ensure installer efficiency and long-term maintainability in demanding solar and ESS environments.

Applications & Use Cases

Kuangya DC MCB delivers reliable DC circuit protection for solar PV, ESSy EV charging escenarios. Aísla los fallos, protege los inversores/baterías y se coordina con Fusibles CC, DC SPD, and Seccionadores de CC en Cajas de conexiones fotovoltaicas.

Residential Rooftop Solar

String-level DC MCB for 600–1000V PV rooftops; ideal with Fusible CC + SPD coordination.

Commercial & Industrial PV Arrays

High-current feeders protected by DC MCB 1000V for C&I rooftops and carports.

Ground-Mounted Solar Systems

Combiner arrays using miniature DC circuit breakers for safer maintenance.

ESS Battery Racks & Containers

Protection up to 125A; integrates with BMS and DC distribution.

EV Charging Hubs / Carports

Protects feeders in EV charging sites with upstream disconnects.

Microgrid & Off-Grid Systems

Rugged solar DC MCB ensures isolation for remote microgrids in harsh conditions.

Guía de aplicación

Not sure which DC MCB to choose? Use the quick guidance below. These pair well with Fusible CC, DC SPD, DC Switch Disconnectors y Cajas combinadoras FV for a coordinated protection scheme.

63A

Residential Rooftop PV

Small PV arrays (up to ~10 kW), string protection

  • Recomendado: KYDB-63 (1P / 2P / 3P / 4P)
  • Typical: 250–1000VDC, fast arc quenching
  • Place at string/feeder; coordinate with DC Fuses & SPDs
125A

Commercial & Industrial Rooftop

Multiple strings, higher feeder current

  • Recomendado: KYDB-125 (1P / 2P)
  • Feeder & sub-array protection up to 125A
  • Coordinate with upstream Seccionadores de CC
125A

Ground-Mounted / Utility PV & ESS

Large combiner outputs, DC bus & containerized ESS

125A

EV Charging Hubs / Carports

DC feeders & auxiliaries in EV charging sites

  • Recomendado: KYDB-125 (2P / 4P)
  • Coordinate with DC SPD and upstream isolation
  • Label & document per IEC / UL practice

* Final sizing depends on IEC 60947-2 / UL 489 compliance, cable ampacity, fault level and system architecture. Need help? Talk to our engineers.

Wiring & Installation Guide

Practical notes for installing DC MCB in solar PV, ESS y EV charging systems. Coordinate the breaker with Fusibles CC, DC SPD, Seccionadores de CC y Cajas de conexiones fotovoltaicas.

Wiring Accessories

  • MC4 leads / ring or fork lugs for PV strings and feeders.
  • Comb busbar (phase combs) or Cu links for multi-pole bridges.
  • Carril DIN EN 60715 mounting; allow air gaps for heat dissipation.
  • Use the correct par de torsión for terminals (see datasheet); re-check after 24–48 h.

Cabling & Protection

  • Size cables by continuous current + temperature derating.
  • Keep feeder runs short and avoid tight bundles to reduce temperature rise.
  • For strings: MCB provides isolation; coordinate with a gPV fuse.
  • Add upstream SPD y main disconnector.

Polarity & Labeling

  • Clearly label + / −, pole count and VDC rating at the device.
  • Utilice handle-tie kits when poles must trip together (2P/3P/4P).
  • Keep minimum bend radius; route away from sharp edges and hot surfaces.
  • Record settings, torque and test results in the O&M log.

Typical DC Voltage by Pole Configuration

Values below reflect common system groupings for Kuangya KYDB series; always verify the exact rating on the product label and the datasheet (IEC 60947-2 / UL 489).

Pole option
Typical VDC
Typical application
1P
250 V DC
Small DC panels, auxiliaries, single-pole isolation
2P
500 V DC
PV strings (±), EV auxiliaries, balanced two-wire feeders
3P
750 V DC
ESS rack segments, higher-voltage sub-arrays
4P
1000 V DC
PV combiner outputs, containerized ESS / DC distribution
Why does the allowable DC voltage increase with more poles?

Multi-pole DC MCBs place poles in series so the total arc distance is increased and the voltage stress is divided across internal arc chambers. For example, 2P ≈ 500 VDC and 4P ≈ 1000 VDC for the KYDB series. Note that breaking capacity still follows the device rating—adding poles does not multiply the short-circuit rating. Always use the manufacturer’s approved pole kits so the poles trip together.

Can I wire poles in en paralelo to increase current?

Parallel poles are not recommended unless explicitly stated by the manufacturer. Unequal impedance causes current imbalance and nuisance tripping. Choose the correct frame (e.g. KYDB-125) and size cables per derating instead.

Why Choose Kuangya for DC MCBs

Factory-tested DC miniature circuit breakers engineered for solar PV, ESS y EV charging. Certified to IEC 60947-2 / UL 489, with rapid delivery and OEM options.

Factory-Direct & Certified

Own manufacturing with ISO 9001 QA. Batch test against IEC 60947-2 / UL 489.

Visit our factory →

High-Voltage Type Testing

Pruebas de temple al arco para 1000VDC / 125A. Routine inspection & traceability reports.

See quality program →

Plazo de entrega rápido

Stock on key poles. Typical delivery 7–15 days. Global shipping support.

Check availability →

OEM / ODM Ready

Etiqueta privada, postes personalizados, marcas de tensión y embalajes a juego con su línea.

Explore OEM options →

Global Project Experience

Deployed in PV farms, C&I rooftops, ESS containers & EV hubs across 30+ regions.

View case studies →

DC MCB FAQ

Frequently asked questions about DC MCB applications in solar PV, ESS y EV charging. Covering voltage, breaking capacity, fuse coordination, SPD protection, switch disconnectors, and compliance with IEC 60947-2 / UL 489.

1. What is a DC MCB and how does it work?

A DC MCB (Miniature Circuit Breaker) provides overcurrent and short-circuit protection in direct current systems such as solar PV, ESS, and EV charging. It interrupts the DC arc safely to protect equipment and cables.

2. What are the typical applications of a DC MCB?

They are used in solar rooftops, ground-mounted PV arrays, ESS battery racksy EV charging hubs to ensure reliable circuit protection.

3. How is the rated voltage defined?

The rated voltage increases with the number of poles: 1P=250VDC, 2P=500VDC, 3P=750VDC, 4P=1000VDC. This enables flexible design for different PV and ESS voltages.

4. Can DC MCBs be used in parallel?

Not recommended unless approved by the manufacturer. Parallel poles may cause current imbalance. Instead, select the correct frame size such as KYDB-125 and follow IEC 60947-2 guidelines.

5. How to size a DC MCB for PV strings?

Choose a current rating above the PV string short-circuit current (Isc). Check breaking capacity, coordination with Fusibles CC, and compliance with UL 489 / IEC 60947-2 standards.

6. What is the breaking capacity of Kuangya DC MCBs?

Kuangya breakers are rated up to 6kA at 1000VDC, ensuring safe disconnection under fault conditions for both residential and utility-scale PV systems.

7. What are the installation requirements?

DIN-rail mounted per EN 60715. Use proper torque for terminals, MC4 leads or busbars for secure wiring, and maintain clear polarity labeling (+/−).

8. Are DC MCBs compliant with global standards?

Yes. They comply with IEC 60947-2 y UL 489, meeting global certification requirements.

9. Can DC MCBs be combined with other protective devices?

Sí, a menudo se coordinan con SPDs, fusesy switch disconnectors en Cajas de conexiones fotovoltaicas to form a complete protection stack.