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MERSEN FUSE NH4A400KVA GTR NH4A2GTR400KVA NH4A2GTR400KVA
Mersen NH4A2GTR400KVA NH4a gTr fuse-link for the overload and short-circuit protection of 400 kVA three-phase distribution transformers operating at 400 V AC.
£101.62
Why Choose the Mersen NH4A2GTR400KVA Transformer Protection Fuse-Link?
The Mersen NH4A2GTR400KVA is a specialist DIN NH gTr fuse-link designed to protect low-voltage distribution transformers against overloads and short-circuit faults. Part of Mersen's professional NH gTr 400 V AC transformer protection range, it features an operating characteristic specifically matched to transformer behaviour.
The gTr characteristic enables the fuse-link to tolerate normal transformer magnetising inrush currents while providing dependable current-limiting protection during sustained overloads and severe electrical faults. It also supports effective selectivity with downstream gG fuse-links, helping isolate affected circuits without unnecessarily interrupting the wider installation.
Designed for 400 kVA three-phase transformers, the NH4A2GTR400KVA has a nominal current rating of approximately 577 A at 400 V AC. Its NH4a construction, centre indicator and live gripping lugs make it suitable for transformer incomers, industrial substations and main low-voltage distribution switchboards.
Key Advantages
- Purpose-designed for low-voltage distribution transformer protection.
- Matched to 400 kVA three-phase transformer applications.
- 577 A nominal current rating at 400 V AC.
- gTr characteristic accommodates normal transformer energisation currents.
- Provides effective overload and short-circuit fault protection.
- Supports selectivity with downstream gG protection devices.
Key Features
- Mersen NH gTr transformer fuse-link range.
- Catalogue number: NH4A2GTR400KVA.
- Manufacturer reference: G1030521.
- NH4a fuse format.
- 400 kVA transformer rating.
- Approximately 577 A nominal current.
- 400 V AC rated operating voltage.
- gTr full-range transformer protection characteristic.
- Centre-mounted fuse operation indicator.
- Live gripping lugs for use with a suitable NH fuse puller.
- DIN NH blade-contact construction.
- Designed for installation by qualified electrical professionals.
Reliable Protection for Distribution Transformers
Transformer energisation can produce a short-duration magnetising current significantly greater than the normal operating current. The Mersen NH4A2GTR400KVA is designed to withstand this expected inrush without unnecessary operation while remaining responsive to genuine overload and short-circuit conditions.
Its current-limiting performance helps reduce thermal and electrodynamic stress on transformers, conductors and switchgear during a fault. The dedicated gTr characteristic also assists coordination with downstream protective devices, supporting reliable and selective operation across the distribution system.
Typical Applications
- Protection of 400 kVA distribution transformers.
- Industrial and commercial substations.
- Transformer incomer circuits.
- Main low-voltage switchboards.
- Factory and process power distribution systems.
- Utility and infrastructure electrical installations.
Technical Specifications
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| Fuse Indication | Visual indicator | |
|---|---|---|
| Device Type | Fuse link | |
| Fuse Type | NH (DIN) | |
| Fuse Size | NH4a | |
| Fuse Class | gTr | |
| Voltage | 400 V | |
| Manufacturer | Mersen | |
| Series | NH Fuse-Links gTr 400 VAC | |
| Model | NH4A2GTR400KVA | |
| Item number | G1030521 | |
| Product type | DIN NH transformer protection fuse-link | |
| Fuse size | NH4a | |
| Transformer rating | 400 kVA | |
| Nominal current | Approx. 577 A | |
| Rated voltage | 400 V AC | |
| Operating characteristic | gTr | |
| Indication system | Centre indicator | |
| Gripping-lug design | Live gripping lugs | |
| Contact format | DIN NH blade contacts | |
| Installation | Compatible NH fuse-base or fuse-switch disconnector | |
| Application | Three-phase distribution transformer protection |
Frequently Asked Questions
What is the Mersen NH4A2GTR400KVA used for?
The NH4A2GTR400KVA is designed to protect 400 kVA low-voltage distribution transformers against overloads and short-circuit faults.
What is the nominal current rating of this fuse-link?
The fuse-link has a nominal current rating of approximately 577 A for a 400 kVA three-phase transformer operating at 400 V AC.
What voltage is the NH4A2GTR400KVA rated for?
The Mersen NH4A2GTR400KVA is designed for transformer protection applications operating at 400 V AC.
What does the gTr operating characteristic mean?
The gTr characteristic is designed specifically for transformer protection. It accommodates normal transformer inrush currents while providing full-range protection against overloads and short circuits.
Who should install or replace this NH fuse-link?
Because NH fuse systems contain exposed conductive components and do not inherently prevent the installation of an incorrect current rating, the fuse-link should only be installed or replaced by a qualified electrical professional using suitable protective equipment.
Trusted by Power Distribution Professionals
Mersen NH gTr fuse-links are widely specified by electrical engineers, panel builders and infrastructure operators for dependable transformer protection, effective fault-current limitation and reliable coordination within low-voltage distribution systems.
