Why Choose the Mersen K1000279 High Voltage DIN Back-up Fuse?
The Mersen K1000279 is a premium DIN high voltage back-up fuse designed to provide dependable short-circuit protection for medium voltage transformers operating in electrical distribution systems. Part of the advanced Mersen Limitor®-PTD series, it incorporates Controlled Power Dissipation (CPD) technology together with an integrated thermal striker, making it ideal for modern air-insulated and gas-insulated switchgear applications.
Designed in accordance with IEC 60282-1 and VDE 0670 T402, the K1000279 delivers outstanding current-limiting performance whilst reducing thermal and mechanical stress during fault conditions. Manufactured using pure silver fuse elements, silver-plated copper end caps and a ceramic body, it provides long service life and dependable operation in demanding medium voltage environments.
With a rated voltage of 24 kV AC, a 25 A current rating and an integrated 80 N thermal striker, the Mersen K1000279 is ideally suited for transformer protection in substations, industrial facilities and utility distribution networks where high reliability is essential.
Key Advantages
- Designed specifically for medium voltage transformer protection.
- 24 kV AC rated voltage for demanding electrical systems.
- 25 A rated current for compatible transformer installations.
- Controlled Power Dissipation (CPD) technology helps reduce operating temperatures.
- Integrated 80 N thermal striker for compatible switchgear mechanisms.
- High current-limiting capability reduces equipment damage during faults.
Key Features
- Mersen Limitor®-PTD high voltage DIN back-up fuse.
- Catalogue number: 45DB240V25PTD.
- 24 kV AC rated voltage.
- 25 A rated current.
- 56 mm diameter × 442 mm length.
- Integrated 80 N thermal striker.
- Controlled Power Dissipation (CPD) construction.
- Suitable for transformer protection in air and gas insulated switchgear.
High voltage back-up fuse-links rapidly interrupt high fault currents before they can damage transformers and associated switchgear. Their current-limiting characteristics help minimise thermal and mechanical stress, improving equipment reliability whilst reducing maintenance requirements.
The Mersen Limitor®-PTD range combines high breaking capacity with Controlled Power Dissipation technology, reducing operating temperatures whilst maintaining excellent protection performance. This makes the range particularly suitable for compact switchgear and modern transformer installations.
Typical Applications
- Medium voltage transformer protection.
- Air-insulated switchgear.
- Gas-insulated switchgear.
- Electrical substations.
- Industrial power distribution systems.
- Utility infrastructure.
