Why Choose the Mersen HSJ400 High Speed Class J Fuse?
The Mersen HSJ400 is a high performance Class J high speed semiconductor fuse designed to provide branch circuit protection alongside low let-through energy for sensitive power electronic components. As part of the established Mersen Amp-Trap HSJ Series, it combines the protective characteristics of a semiconductor fuse with the branch circuit performance of a UL Listed Class J fuse.
The HSJ400 is engineered to interrupt damaging fault currents rapidly, helping protect diodes, SCRs, GTOs, solid state relays and other semiconductor devices. Its high speed operating characteristic limits the thermal and electrical energy passed to protected equipment, reducing the risk of component damage, costly repairs and unplanned industrial downtime.
With a rated current of 400 A, an AC voltage rating of 600 V and a DC voltage rating of 500 V, the Mersen HSJ400 is suitable for variable frequency drives, soft starters, power conversion equipment and industrial control systems. Its blade terminals and clip-mounted format provide secure installation in compatible Class J fuse holders and approved electrical equipment.
Key Advantages
- High speed Class J fuse for semiconductor and branch circuit protection.
- 400 A current rating for demanding industrial power applications.
- 600 V AC and 500 V DC ratings for AC and DC circuits.
- Low I²t performance helps protect sensitive semiconductor components.
- High 200 kA AC interrupting capacity for severe fault conditions.
- Heavy-duty blade terminals provide secure clip-mounted installation.
Key Features
- Mersen Amp-Trap HSJ high speed fuse series.
- 400 A rated current.
- 600 V AC / 500 V DC rated voltage.
- 50 / 60 Hz operating frequency.
- Class J branch circuit protection.
- Low let-through energy for semiconductor protection.
- 200 kA maximum AC interrupting rating.
- Brass blade terminals for reliable electrical connection.
Reliable Protection for Industrial Power Electronics
High speed fuses such as the Mersen HSJ400 are designed to interrupt short-circuit currents before excessive fault energy can damage sensitive semiconductor components. By limiting peak current and let-through energy, the fuse helps protect electronic switching devices that can be more vulnerable to overcurrent conditions than conventional electrical equipment.
The HSJ400 combines Class J branch circuit performance with high speed semiconductor protection, helping simplify industrial electrical system design. It is particularly suitable for high-current applications involving motor drives, power conversion assemblies and electronic control equipment.
Typical Applications
- Variable frequency drives and motor controllers.
- Industrial control panels and automation systems.
- Soft starters and solid state relays.
- Power converters, inverters and rectifiers.
- SCR, GTO and diode protection circuits.
- Industrial power supplies and OEM machinery.
