Why Choose the Mersen NH4AGTR250KVA Transformer Protection Fuse?
The Mersen NH4AGTR250KVA is a high-performance DIN NH gTr fuse link developed specifically for protecting low-voltage distribution transformers. Its transformer-specific operating characteristic accommodates normal magnetising inrush currents while providing dependable interruption during overload and fault conditions.
Part of the Mersen NH gTr 400 V transformer fuse range, this NH4a fuse link features a robust ceramic body, blade contacts, live gripping lugs and a central fuse-operation indicator. The indicator allows maintenance personnel to identify an operated fuse quickly, while its standard NH construction supports installation in a compatible NH4a fuse base or switch-fuse assembly.
Designed for 250 kVA transformers, the NH4AGTR250KVA has a rated current of 361 A and a rated operating voltage of 400 V AC. It is suited to industrial, commercial and infrastructure power distribution systems where reliable transformer protection and coordinated selectivity are essential.
Key Advantages
- Purpose-designed gTr fuse link for transformer protection.
- Matched to 250 kVA low-voltage transformers.
- 361 A rated current for high-capacity distribution systems.
- 400 V AC voltage rating.
- Central indicator provides clear visual confirmation after operation.
- Transformer-specific characteristic supports reliable selectivity with downstream gG fuses.
Key Features
- Mersen NH gTr transformer fuse-link series.
- 250 kVA transformer rating.
- 361 A rated current.
- 400 V AC rated voltage.
- NH Size 4a construction.
- Transformer-specific gTr utilisation category.
- Central fuse-operation indicator.
- Live gripping lugs for use with an approved NH fuse puller.
- Robust ceramic body with blade contacts.
- DIN NH standard configuration.
The gTr time-current characteristic is specially adapted to the operating behaviour of distribution transformers. It allows the fuse to tolerate temporary transformer magnetising currents during energisation while responding reliably to sustained overloads and damaging fault currents.
The NH4AGTR250KVA also supports coordinated selectivity with downstream NH gG fuse links. This helps isolate faults closer to their source, reducing unnecessary interruption to unaffected circuits and improving continuity across industrial and commercial distribution systems.
Typical Applications
- 250 kVA low-voltage distribution transformers.
- Industrial transformer protection panels.
- Commercial power distribution systems.
- Utility and infrastructure installations.
- Main switchboards and transformer feeder circuits.
- OEM substations and packaged transformer assemblies.
