Why Choose the Mersen NH3UD69V550PV Protistor® Semiconductor Fuse?
The Mersen NH3UD69V550PV is a high-speed NH size 3 semiconductor fuse designed to protect sensitive power-electronic components against damaging short-circuit currents. Part of the established Mersen Protistor® range, it is intended for demanding industrial equipment incorporating IGBTs, thyristors, power diodes, rectifiers and other semiconductor devices.
Featuring an aR operating characteristic, the NH3UD69V550PV provides partial-range semiconductor protection with rapid fault interruption and effective current limitation. Its high-speed performance helps reduce peak fault current and let-through energy, limiting the electrical, thermal and mechanical stress imposed on valuable power-electronic components.
With a rated current of 550 A, a rated voltage of 690 V AC under IEC requirements and 700 V AC under UL requirements, and a robust NH size 3 format, this fuse is suitable for high-power variable frequency drives, converters, rectifiers, inverters and industrial power-control systems. Its blade-contact construction enables installation in a correctly rated compatible NH fuse base or fuse-switch disconnector.
Key Advantages
- High-speed Protistor® fuse for semiconductor protection.
- 550 A rated current for high-power industrial equipment.
- 690 V AC IEC and 700 V AC UL ratings.
- aR operating class for rapid semiconductor short-circuit protection.
- Current-limiting performance helps reduce damaging fault energy.
- Standard NH construction supports convenient maintenance and replacement.
Key Features
- Mersen Protistor® high-speed fuse range.
- 550 A rated current.
- 690 V AC IEC / 700 V AC UL rated voltage.
- aR partial-range semiconductor protection characteristic.
- NH size 3 industrial fuse format.
- Square ceramic body with plain blade contacts.
- Low let-through energy during short-circuit conditions.
- Suitable for high-power drives, converters and semiconductor assemblies.
Reliable Protection for High-Power Electronics
Power-semiconductor devices can be permanently damaged by fault energy before a conventional general-purpose fuse has time to operate. The Mersen NH3UD69V550PV is engineered to clear high fault currents rapidly while limiting the peak current and total energy transmitted to the protected circuit.
Its aR characteristic is intended specifically for short-circuit protection rather than full-range overload protection. The fuse should therefore be coordinated with suitable overload protection and selected according to the equipment manufacturer's requirements, operating current, system voltage and prospective short-circuit current.
Typical Applications
- High-power variable frequency drives.
- Industrial inverters and rectifiers.
- AC and DC power converters.
- Uninterruptible power supply systems.
- Motor drives and power-control assemblies.
- Industrial automation and OEM machinery.
