Frequently Asked Questions

You will find answers about GFEFUSE's product technical services. If you do not receive an answer to the question below, please feel free to contact us at any time.

What is the role of the high temperature resistance characteristics of automotive fuses?

It allows the fuse to work normally in the high temperature environment inside the car, and is not easily affected by temperature changes.

Features: It can withstand the frequent instantaneous high pulse current impacts in new energy power generation systems (such as solar panels and wind turbines), and avoid the impact of common fuses on system operation due to frequent melting.
Application scenario: Circuit protection of new energy power generation systems.

In electric vehicles, new energy fuses are the key to ensuring the safety of power systems and electronic equipment: When a circuit fails (such as short circuit, overload), the circuit must be disconnected quickly and accurately to avoid causing serious safety accidents (such as battery fire and explosion).

The fuse is the main component of the fuse, and is often made into a wire, sheet or grid shape. Its materials are divided into two categories:

Low melting point materials (lead, lead-tin alloy, zinc, etc.): mostly used in small current circuits;

High melting point materials (silver, copper, etc.): mostly used in large current circuits.

New energy fuse is a circuit protection component designed specifically for new energy applications (such as electric vehicles, solar power generation, wind power generation, etc.). Its core function is to ensure the circuit safety of the new energy system, prevent short circuits, overloads and other faults from causing safety accidents (such as battery fire and explosion) by quickly and accurately disconnecting the circuit, and provide support for the stable operation of the system.

Regular fuses are designed for AC systems and may not reliably interrupt DC arcs, especially at high voltages. PV fuses (UL 248-19) are optimized for DC interruption and low-fault-current operation.

Check the fuse marking or datasheet. DC‑rated fuses clearly indicate their DC voltage rating. Look for “DC” or “gPV” markings on the fuse body. Never use an AC‑only rated fuse in a DC circuit, as it may fail to interrupt DC arcs safely.

No. Never use a fuse with a voltage rating lower than the system voltage. A fuse with insufficient voltage rating may fail to interrupt the arc during a fault, causing equipment damage or fire. Always match or exceed the system voltage rating.

An oversized fuse may not operate during a fault condition, allowing excessive current to flow through the system and creating fire hazards. Always follow the manufacturer’s sizing guidelines and relevant standards such as NEC 690.9 for PV systems.

gPV fuses (UL 248‑19) provide full‑range protection covering both overload and short‑circuit conditions, developed specifically for photovoltaic systems.


aR fuses (UL 248‑13) only offer short‑circuit protection, mainly used for semiconductor device protection.


For string‑level PV protection, gPV fuses are required instead of aR fuses.


Breaking capacity refers to the maximum short‑circuit current that a fuse can safely cut off under rated DC voltage. If the actual short‑circuit current exceeds the fuse breaking capacity, the fuse may fail to extinguish the electric arc, which will lead to burning or fire hazards. Always select fuses whose breaking capacity is higher than the system prospective short‑circuit current.

Most bolt‑on DC fuses are non‑polarized, they can be installed in either direction of the circuit. However, please strictly follow the installation direction marked on the fuse housing and product datasheet. Wrong installation will not blow the fuse normally under fault conditions.

Premature blowing is usually caused by multiple factors: frequent pulse current overload, high ambient temperature, poor contact of mounting terminals, aging of the fuse element, or selecting a fuse with too small rated current. It is necessary to re‑check system current, ambient temperature and torque of bolt terminals.

Bolt‑on fuses adopt bolt fixing connection, featuring low contact resistance, good heat dissipation performance, suitable for high‑current energy storage and new energy vehicle systems. Cartridge fuses rely on spring clip contact, which are more suitable for small‑current photovoltaic string protection. Select the structure according to actual current and installation requirements