Why Choose the Mersen HSJ225 High-Speed Class J Fuse?
The Mersen HSJ225 is a 225 A High-Speed Class J fuse engineered to provide both branch-circuit protection and rapid semiconductor protection in demanding industrial applications. As part of the Mersen Amp-Trap® HSJ series, it combines the low I²t performance of a semiconductor fuse with the branch-circuit capabilities of a UL Listed Class J fuse, making it ideal for protecting modern power-electronic equipment.
Designed for industrial automation and power conversion systems, the HSJ225 delivers rapid fault interruption while withstanding elevated inrush currents associated with electronic motor controllers and variable frequency drives. Its current-limiting design helps minimise thermal stress and reduce damage to valuable electrical equipment.
Rated at 225 A, 600 V AC and 500 V DC, the HSJ225 is suitable for protecting drives, soft starters, UPS systems, rectifiers, inverters, SCRs, diodes, GTOs and other semiconductor-based equipment.
Key Advantages
- Provides both Class J branch-circuit and semiconductor protection.
- 225 A rated current for demanding industrial power applications.
- 600 V AC / 500 V DC voltage ratings.
- Low I²t characteristics reduce thermal stress on power semiconductors.
- Excellent cycling capability for frequent equipment starts and stops.
- 200 kA AC interrupting rating for high fault-current installations.
Key Features
- Mersen Amp-Trap® HSJ series.
- 225 A current rating.
- 600 V AC and 500 V DC rated.
- High-speed Class J operating characteristic.
- Current-limiting design.
- Blade terminal construction.
- Optimised overload capability for electronic motor-controller starts.
- Suitable for approved Class J fuse holders and fuse blocks.
High-Speed Protection for Industrial Power Electronics
The Mersen HSJ225 combines the branch-circuit protection required by electrical codes with the very low let-through energy needed to protect sensitive semiconductor devices. It rapidly clears short-circuit faults before excessive electrical and thermal energy can damage SCRs, GTOs, IGBTs, diodes and solid-state relays.
Its optimised overload capability enables reliable operation during the elevated currents experienced during electronic motor-controller starting while maintaining outstanding current-limiting performance during fault conditions.
Typical Applications
- Variable frequency drives (VFDs).
- Electronic motor controllers.
- Soft starters.
- Industrial rectifiers and inverters.
- Power converters.
- UPS systems.
- Industrial control panels.
- Solid-state relay protection.
