MERSEN FUSE H 1209UP BCKUP T292-56/50 45DB120V50PT

MERSEN FUSE H 1209UP BCKUP T292-56/50 45DB120V50PT

Mersen X1000129 Limitor-PT high voltage DIN back-up fuse-link with controlled power dissipation, rated at 12 kV AC and 50 A for transformer protection.

SKU: X1000129Alt SKU: 45DB120V50PTMPN: X1000129
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List Price £119.68 ex VAT
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Why Choose the Mersen X1000129 Limitor®-PT High Voltage Back-up Fuse?

The Mersen X1000129 is a premium Limitor®-PT high voltage DIN back-up fuse-link with controlled power dissipation, specifically engineered for protecting medium voltage transformers against short-circuit faults. Manufactured in accordance with IEC 60282-1, it combines dependable fault interruption with reduced thermal loading, making it ideal for modern medium voltage switchgear installations.

Part of the trusted Mersen Limitor®-PT range, the X1000129 features pure silver fuse elements, silver-plated copper terminals and a robust ceramic body to deliver excellent electrical performance and a long operating life. The integrated 80 N controlled power dissipation (CPD) striker provides reliable operation with compatible switchgear and transformer protection equipment.

Rated at 12 kV AC with a 50 A current rating, the X1000129 is supplied in a compact 56 mm × 292 mm DIN format, making it suitable for transformer protection in industrial substations, utility networks and medium voltage distribution systems.

Key Advantages

  • Designed specifically for medium voltage transformer protection.
  • Controlled power dissipation technology helps reduce thermal loading.
  • 12 kV AC rated voltage for medium voltage electrical systems.
  • 50 A rated current for transformer primary protection.
  • Integrated 80 N CPD striker for dependable switchgear operation.
  • Manufactured using premium silver fuse elements and ceramic construction.

Key Features

  • Mersen Limitor®-PT back-up fuse-link.
  • Catalogue number: 45DB120V50PT.
  • Rated voltage: 12 kV AC.
  • Rated current: 50 A.
  • Breaking capacity: 63 kA.
  • Fuse dimensions: 56 mm diameter × 292 mm length.
  • 80 N controlled power dissipation striker.
  • Designed for transformer protection in medium voltage switchgear.

Reliable Protection for Medium Voltage Transformers

Medium voltage back-up fuse-links rapidly interrupt damaging fault currents before they can affect transformers and associated switchgear. Controlled power dissipation technology reduces operating temperatures within enclosed switchgear, improving equipment reliability and extending service life.

The Mersen Limitor®-PT range has been developed for dependable transformer protection in industrial facilities, substations and utility distribution networks where consistent performance and reduced thermal stress are essential.

Typical Applications

  • Medium voltage transformer protection.
  • Industrial substations.
  • Medium voltage switchgear.
  • Utility distribution networks.
  • Commercial power distribution.
  • Renewable energy infrastructure.

Technical Specifications

Voltage 120 V
Manufacturer Mersen
Series Limitor®-PT
Model X1000129
Catalogue number 45DB120V50PT
Product type High voltage DIN back-up fuse-link
Rated voltage 12 kV AC
Rated current 50 A
Frequency 50 / 60 Hz
Breaking capacity 63 kA
Minimum breaking current 160 A
Clearing I²t at rated voltage 34.9 kA²s
Fuse dimensions Ø56 × 292 mm
Striker Controlled power dissipation, 80 N
Construction Ceramic body with pure silver fuse elements and silver-plated copper terminals
Applicable standard IEC 60282-1
Weight Approx. 1.6 kg
HS Code 85351000
Device Type Fuse link
Fuse Type High voltage
Current 50 A

Frequently Asked Questions

What is the Mersen X1000129 used for?

The X1000129 is a high voltage DIN back-up fuse-link designed to protect medium voltage transformers against damaging short-circuit currents.

What voltage is this fuse rated for?

This fuse is rated for operation on 12 kV AC systems.

What is the current rating?

The Mersen X1000129 has a 50 A rated current.

What is controlled power dissipation?

Controlled power dissipation technology helps reduce heat generated during normal operation, making the fuse suitable for enclosed medium voltage switchgear.

Does this fuse include a striker?

Yes. It incorporates an integrated 80 N controlled power dissipation striker for reliable indication and operation with compatible switchgear.

Trusted by Electrical Engineers Worldwide

Mersen Limitor®-PT high voltage fuse-links are trusted by utilities, transformer manufacturers and industrial engineers for dependable transformer protection, reduced thermal loading and reliable fault interruption in demanding medium voltage applications.

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