Description
Fast-acting clearance of low-level reverse currents.
Mersen HP10M20 is an industrial 1,000 V DC / 20 A cylindrical gPV photovoltaic string fuse link engineered to protect modern high-power solar strings against reverse-current back-feeding and short-circuit faults with a massive 50 kA DC breaking capacity.
Full-Range gPV Solar Characteristic
Specifically tuned to clear low-level reverse overcurrents and heavy direct-current short circuits characteristic of parallel solar strings.
1,000 V DC Rated Operating Voltage
Safely interrupts high-voltage direct currents without sustaining dangerous ionization arcs.
50 kA DC High Breaking Capacity
Withstands extreme short-circuit fault energies from multi-megawatt commercial solar arrays.
Low Power Dissipation & High Thermal Stability
High-grade silver fuse element ensures minimal internal $I^2R$ heat losses in hot rooftop combiner boxes.
More product details
Standard AC fuses fail to interrupt direct-current solar faults because DC power does not cross zero volts. The HP10M20 features pure silver elements embedded in high-purity silica sand to quench DC arcs instantly.
- Certified gPV curve clears faults between 1.35 × In up to full 50 kA short circuits.
- Protects solar modules from destructive back-feeding currents when one string is shaded or shorted.
- Silver fuse element ensures ultra-low internal resistance and low operating temperature.
Universal compatibility with standard modular fuse holders.
Designed as an industry-standard 10 × 38 mm cylindrical cartridge, it integrates seamlessly into standard DIN-rail fuse holders. High-grade ceramic body withstands high internal thermal shock and arc pressures. Silver-plated copper end caps ensure low contact resistance and corrosion immunity. Universal fit for Mersen UltraSafe CUS101HEL fuse holders.
Fits a 10x38 mm holder
The link is 10 x 38 mm. Catalogue number is HP10M20.
Holds 50 kA interrupt
The rating is 50 kA at 1000 V DC. The class is gPV.
Sits at 2.8 W at full current
70 percent is 1.1 W. 80 percent is 1.5 W. Manufacturer reference is P1018591.
Technical data
Precision DC overcurrent isolation engineered to protect solar modules against reverse-feed faults.
1000 V DC / 20 A dedicated gPV solar fuse link for string overcurrent protection.
Purpose-engineered for photovoltaic string protection, the Mersen HelioProtection HP10M20 provides fast-acting overcurrent and reverse-current isolation at 1000 V DC. Sized at 20 A in a standard 10 × 38 mm format, it protects individual solar strings against back-feeding faults from adjacent parallel strings without nuisance tripping during normal generation peaks.
- Max Operating
- 1,000 V DC
- Rated Current
- 20.0 A
- Breaking Rating
- 50 kA DC
- IEC 60269-6
- gPV Standard
Fuse link
- Size
- 10 x 38 mm, midget
- Rated voltage
- 1000 V DC
- Rated current
- 20 A
- Class
- gPV, special purpose
- Interrupting rating
- 50 kA
Power loss
- Watts loss at 70% of In
- 1.1 W
- Watts loss at 80% of In
- 1.5 W
- Watts loss at 100% of In
- 2.8 W
Application
- Designed for
- Photovoltaic string wiring protection at 1000 V DC
- Cycling
- Withstands the temperature cycling of PV service, for system longevity
- Breaking
- Capable of interrupting the low fault currents typical of PV strings
Logistics
- Catalogue number
- HP10M20
- Manufacturer reference
- P1018591
Project fit
Where this model fits.
Scenarios that show which projects the Mersen HP10M20 (20 A gPV string fuse, 10x38 mm, 1000 V DC) belongs in, what to verify before quoting, and when another model is the better pick.
String Overcurrent Protection on 2+ Parallel PV Strings per MPPT
Solar arrays where 2 or more strings are paralleled into a single inverter MPPT, requiring string fusing under IEC 60364-7-712.
20 A rating provides the necessary safety margin for modern 13–15 A Imp solar modules while tripping reliably before reverse currents damage panels.
- Confirm this model against the adjacent rating in the same family
Documents
Mersen HP10M 1000 VDC PV fuse datasheet (EN, HP10M20 row) DS-HP10M-HelioProtection-Photovoltaic-Fuses-MersenProduct questions
When are string fuses mandatory in a solar installation?
Whenever 3 or more strings are connected in parallel to a single MPPT (or 2 strings if module reverse-current rating is exceeded). Under IEC 60364-7-712, when 3 or more strings are paralleled, a fault in one string can cause the other strings to back-feed into the faulted string, exceeding the module's maximum reverse-current limit ($I_{RCM}$). Installing 20 A gPV fuses on each string eliminates this fire risk.