Why Choose the Mersen A4J100 Class J Fast-Acting Fuse?
The Mersen A4J100 is a premium Class J fast-acting fuse designed to provide superior overcurrent and short-circuit protection for industrial and commercial electrical systems. Part of the trusted Mersen Amp-Trap® A4J series, it is ideal for feeder circuits, switchboards, panelboards, bus duct systems and general-purpose branch circuit protection.
Rated at 100 A, 600 V AC and 300 V DC, the A4J100 combines excellent current-limiting performance with high interrupting capacity. Its fast-acting characteristic rapidly clears fault currents before they reach damaging levels, helping protect conductors, switchgear and connected equipment.
The A4J100 features the unique Class J rejection design, preventing replacement with lower-rated fuse classes while providing dependable protection for sensitive electrical equipment and industrial power distribution systems.
Key Advantages
- High-performance Class J fast-acting protection.
- 100 A current rating for industrial and commercial applications.
- 600 V AC / 300 V DC voltage ratings.
- Current-limiting design reduces peak fault current and let-through energy.
- Fast operation protects sensitive electrical equipment.
- Class J rejection dimensions help prevent incorrect fuse replacement.
- Fibreglass body provides excellent dimensional stability.
Key Features
- Mersen Amp-Trap® A4J series.
- 100 A rated current.
- 600 V AC rated voltage.
- 300 V DC rated voltage.
- Class J current-limiting fuse.
- Fast-acting operating characteristic.
- 200 kA AC interrupting rating.
- 100 kA DC interrupting rating.
- Knife blade terminals.
- Fibreglass body construction.
- Suitable for 50 / 60 Hz electrical systems.
- RoHS and REACH compliant.
Fast Current-Limiting Protection
The Mersen A4J100 is engineered to clear fault currents rapidly, significantly reducing peak let-through current and energy. This helps minimise thermal and mechanical stress on downstream equipment, improving overall system reliability and reducing the risk of costly damage.
Its fast-acting design makes the A4J100 particularly suitable for protecting circuits containing sensitive electrical equipment where rapid fault interruption is required. The compact Class J rejection design also enhances installation safety by preventing substitution with lower-performance fuse classes.
Typical Applications
- Industrial control panels.
- Panelboards.
- Switchboards.
- Bus duct systems.
- Feeder circuits.
- Circuit breaker protection.
- Capacitor protection.
- Lighting and heating circuits.
- General industrial electrical loads.
