What to send for a solar DC fuse quotation
A photovoltaic fuse quotation needs the system DC voltage, the string current, the fuse format and holder, and the standard the installation must meet. gPV is a distinct utilization category for photovoltaic duty and is not interchangeable with general-purpose or semiconductor categories.
Who this is for: Solar EPC contractors, combiner box manufacturers and PV system designers.
Why PV duty needs its own fuse category
A photovoltaic array is a current-limited DC source. Fault currents are low relative to conventional AC systems, and the fuse has to interrupt DC without a natural current zero. The gPV utilization category exists specifically for this behaviour.
A general-purpose gG fuse or an aR semiconductor fuse of the same ampere rating is not a substitute.
What to send us
Everything below is usually available from the array design and the combiner schedule:
- Maximum system DC voltage, including the open-circuit voltage at the lowest expected temperature
- String short-circuit current and the number of strings in parallel
- Required fuse ampere rating, if already determined by the design
- Fuse format — cylindrical size, or holder and base type
- Whether you need the fuse only, or fuse and base together
- Applicable standard for the installation
- Ambient temperature range and enclosure type
- Quantity and required-by date
Where sizing comes from
PV string fuse sizing follows from the array design and the applicable installation standard, not from the fuse catalogue. We can confirm what we are able to supply against a rating you specify, and flag anything that looks inconsistent with the rest of the information you send.
Limits of this guide
- This guide prepares a quotation request. It does not size the protection for your array.
- String and array fuse sizing is determined by the system design and the applicable installation standard.
- Final selection must be confirmed by the system designer or a qualified engineer.
Related products
Sources
- DENCO product catalog, January 2025, pp. 138–140
Technical review
This guide is educational and is not a protection coordination study. Confirm any selection with DENCO engineering.