DC fuse manufacturer

High-reliability DC fuse design, production, and testing

DC fuses provide fast, predictable protection for direct-current circuits by safely interrupting over-current faults and limiting let-through energy (I²t). Typical uses: solar PV strings/combiners, battery energy storage (ESS), EV/charging, semiconductor drives, telecom, and industrial control. A professional DC fuse manufacturer combines precision element design, controlled sand filling, automated assembly, and rigorous validation to deliver safe, durable, standards-compliant products.

DC Fuse Manufacturing Process

1) Requirements & design

Define rated voltage (e.g., 500–1500 VDC), current (1–630 A+), and breaking capacity.
Select characteristic: gPV (PV full-range), aR/gR (semiconductor), EV traction/battery, or general DC.
Choose package & mounting: 10×38 / 14×51 / 22×58 cylindrical, NH000–NH3, EV/semiconductor bolt-down, inline / panel-mount.
Engineer fuse-element geometry (etched/stamped silver or silver–copper), necks/notches for controlled melting, and target I²t window.
Define arc-quenching system: silica sand granulometry, fill density, body material; add striker/indicator and microswitch if required.

2) Material selection

Element: silver or Ag–Cu alloy; optional tin overlay to tune pre-arcing behavior.
Body: alumina ceramic or glass-reinforced thermoset (EV/semiconductor usually ceramic).
End caps/terminals: copper/brass with nickel/tin plating for low contact resistance.
Arc-quenching medium: high-purity silica sand with controlled grain size and moisture.
Accessories: striker pins, microswitches, indicator windows; finger-safe holders (IP20).

3) Precision fabrication

Photo-chemical etching or precision stamping of fuse elements; micro-notch formation and dimensional inspection.
Turning/stamping of caps, knife blades, or busbar ends; surface finishing and cleaning.
Body forming and firing (ceramic) or molding (thermoset) with tight bore/length tolerances.

4) Assembly & sand filling

Mount and tension the element; vacuum-fill body with graded silica sand to target bulk density.
Seal by crimping, laser welding, or brazing; verify leak-tightness.
Laser marking: ratings, DC voltage, characteristic (gPV/aR/gR/EV), date code/QR for traceability.

5) In-process verification

Resistance measurement (mΩ), visual inspection, weight check for fill mass, and X-ray sampling of element/sand distribution.
Indicator/striker travel force and microswitch function where applicable.

Quality Control Measures

Incoming inspection: alloy composition, plating thickness, ceramic density/porosity, sand granulometry & moisture.
Dimensional control: CMM/optical checks for element necks, body length, terminal alignment.
SPC on resistance, fill density, crimp/weld parameters; lot traceability (QR).
Reliability: thermal cycling, vibration/shock (EV/rail), UV/salt-spray (outdoor PV).
Documentation: DFMEA/PFMEA, PPAP, RoHS/REACH materials control.

Essential Manufacturing Equipment

CAD/CAE for thermal–electrical modelling and I²t optimization.
Photo-etch lines or progressive stamping tools; precision welding/brazing/crimping stations.
Vacuum sand-filling machines with density control; drying ovens and moisture analyzers.
Resistance testers, hipot/IR testers, surge/impulse sources, high-current DC test rigs.
Laser marking, X-ray NDT, environmental chambers, endurance cams (indicator life).

Testing Procedures for DC Fuses

Breaking capacity (Icn) at rated VDC: interrupt prospective DC fault currents; verify arc extinction and containment.
Time–current characteristics: melt/clear within specified curves (gPV full-range, aR/gR semiconductor).
I²t performance: pre-arcing and total clearing I²t; let-through energy limits vs. protected device.
Temperature rise & power loss: watts at rated current; terminal temperature limits.
Dielectric & insulation: withstand / IR before & after fault; creepage/clearance in holders.
Environmental & mechanical: vibration/shock, temperature/humidity cycling, UV/salt fog.
Holder tests: torque strength, contact pressure, finger-safe IP20, glow-wire/flammability.
Common standards: IEC 60269 series (incl. gPV & semiconductor), UL 248 series (incl. PV fuses); automotive/EV may reference ISO 8820.

Why Work with a Custom DC Fuse Manufacturer

Exact ratings and characteristics matched to PV strings, battery racks, DC busbars, drives, or SiC devices.
Package customization (10×38 / 14×51 / 22×58 / NH / EV bolt-down), indicators & microswitches.
Optimized I²t and power loss for your coordination study; support for IEC/UL certification.
Lower lifecycle cost via fewer nuisance trips and reduced downtime.

Experienced DC Fuse Makers Deliver More

Proven element geometries, sand-control know-how, and high-energy DC test capability—plus application support for coordination with contactors, breakers, and protection relays.

Cost-Effective Manufacturing Solutions

Automated filling, high-speed stamping/etching, and localized supply chains keep pricing competitive while maintaining compliance and full traceability.

Adaptable Production Capabilities

Portfolio: 10×38/14×51/22×58 gPV links (up to 1500 VDC), NH gPV, aR/gR semiconductor fuses, EV battery/traction fuses, DC fuse holders & DIN-rail bases.
Branding/marking customization, special holder colors, OEM/ODM packaging.
Accessories: striker indicators, microswitches, panel clips, finger-safe covers.

Sustainable Manufacturing Practices

Recyclable metals/ceramics with closed-loop scrap recovery; low-VOC plating and closed-loop rinsing; energy-efficient drying/sintering; moisture-controlled sand handling to reduce waste.

Advantages of Partnering with Chinese Manufacturers

Robust tooling/molding/stamping ecosystems → short lead times and competitive pricing; high-volume capacity on popular sizes; experience with PV/ESS/EV documentation and IEC/UL files.

How to Choose the Right DC Fuse Manufacturer

Compliance proof: IEC/UL reports for your voltage/characteristic; holder certifications.
DC lab capability: fault-current interruption at your VDC; I²t characterization.
Engineering support: coordination studies, power-loss/temperature charts, application notes.
Quality system: ISO 9001, SPC on resistance/fill density, full lot traceability.
Customization & service: indicators, microswitches, labeling; clear warranty & logistics.

controlled sand filling and rigorous validation to deliver safe, durable, standards-compliant protection up to 1500 VDC.

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Product Portfolio

Cylindrical: 10×38 / 14×51 / 22×58 (up to 1500 VDC, 1–50 A+)
NH gPV: NH000–NH3 for high-current PV/ESS buses
Semiconductor aR/gR: ultra-fast links for power electronics
EV battery/traction: bolt-down designs for high fault energy
Holders & bases: DIN-rail, finger-safe IP20, microswitch options

Key Advantages

IEC/UL compliance with full lot traceability (QR) (IEC standardhttps://webstore.iec.ch/publication/2639)
Custom ratings & I²t to fit your coordination study
Low power loss and tight resistance tolerance
Fast lead time from in-house tooling and automated filling
Engineering support: selection, coordination, and documentation

Applications

PV strings & combiners · Central/Hybrid inverters · ESS racks & DC buses · EV/OBC/fast chargers · Drives & rectifiers · Telecom DC plants

How We Build Reliable DC Fuses

Requirements & Design

Define VDC / In / Icn, select characteristic (gPV / aR / gR / EV), choose package & mounting (10×38, 14×51, 22×58, NH, bolt-down), engineer element geometry and I²t window.

Materials

Silver/Ag-Cu elements · Alumina ceramic or thermoset bodies · Nickel/tin-plated copper/brass terminals · High-purity silica sand (controlled grain & moisture).

Precision Fabrication & Assembly

Photo-etching or stamping → vacuum sand-fill to target density → crimp/laser weld/braze sealing → laser marking with date code/QR.

Testing & Quality

Resistance & power-loss, time-current curves, I²t, breaking capacity at VDC, dielectric/IR, environmental (vibration, humidity, UV, salt fog). Documentation: DFMEA/PFMEA, PPAP, RoHS/REACH.

Why Work With Us (OEM/ODM)

Tailored ratings, I²t and packages for PV/ESS/EV/semiconductor
Holder & accessory ecosystem (striker, indicator, microswitch)
Engineering files (datasheets, derating & coordination charts)
Global shipping and responsive after-sales support

FAQ

Q1: What does “10×38 / 14×51 / 22×58” mean?

They are cylindrical fuse body sizes (diameter × length in mm). Each size supports specific current and voltage ranges.

Q2: What’s the difference between gPV and aR/gR?

gPV covers the full PV operating range and faults. aR/gR are ultra-fast links for semiconductor protection with very low I²t.

Q3: Can an AC fuse be used on DC?

Not reliably. DC requires proven arc-quenching and certified breaking capacity at the rated VDC.

Q4: How do I pick the right fuse for a PV string?

Match VDC to the array max open-circuit voltage, choose In at 1.25–1.56× string current (per standard guidance), and verify Icn and coordination.

Q5: What is I²t and why does it matter?

I²t is the energy let-through during a fault. Lower I²t reduces thermal stress on cables, diodes and semiconductors.

Q6: Do you offer 1500 VDC fuses?

Yes—10×38 gPV up to 1500 VDC in selected ratings, plus NH gPV and EV bolt-down types.

Q7: What certificates can you provide?

IEC 60269 test reports, UL 248 listings (where applicable), RoHS/REACH, material traceability.

Q8: Can I add a striker or microswitch for remote indication?

Yes—striker/indicator and microswitch options are available on many series and holders.

Q9: What’s the typical power loss of a fuse?

Depends on size and rating; we publish watts at rated current and temperature-rise limits in each datasheet.

Q10: Lead time for custom ratings or labels?

Standard links are stocked; custom ratings/labels typically ship quickly thanks to in-house tooling and automated lines.