MERSEN FUSE H 2409UP BCKUP T442-56/20 45DB240V20PT

MERSEN FUSE H 2409UP BCKUP T442-56/20 45DB240V20PT

Mersen L1000142 Limitor PT DIN high voltage back-up fuse-link for transformer protection, rated 24 kV AC, 20 A with controlled power dissipation and 80 N striker.

SKU: L1000142Alt SKU: 45DB240V20PTMPN: L1000142
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List Price £95.44 ex VAT
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Why Choose the Mersen L1000142 High Voltage Transformer Fuse?

The Mersen L1000142 is a high performance Limitor®-PT DIN back-up fuse-link engineered to provide dependable short-circuit protection for medium voltage transformers. Designed in accordance with IEC 60282-1, this fuse forms part of Mersen's trusted Limitor®-PT range, offering controlled power dissipation and reliable protection for electrical distribution systems.

Manufactured using premium materials including pure silver fuse elements, silver-coated copper end caps and a robust ceramic body, the L1000142 delivers consistent performance in demanding utility, industrial and infrastructure applications. Its integrated thermal striker simplifies operation within switchgear and transformer protection systems.

With a 24 kV AC voltage rating, 20 A current rating and 56 mm diameter × 442 mm length construction, the Mersen L1000142 is ideally suited for protecting medium voltage distribution transformers against damaging short-circuit currents while maintaining dependable system reliability.

Key Advantages

  • High voltage DIN back-up fuse-link for transformer protection.
  • 24 kV AC IEC rated voltage.
  • 20 A current rating.
  • Designed in accordance with IEC 60282-1.
  • Controlled power dissipation improves thermal performance.
  • Integrated 80 N thermal striker for reliable operation.
  • High quality ceramic construction with pure silver fuse elements.
  • Suitable for medium voltage switchgear and transformer applications.

Key Features

  • Manufacturer: Mersen.
  • Series: Limitor®-PT Back-up Fuses.
  • Catalogue number: 45DB240V20PT.
  • Rated voltage: 24 kV AC.
  • Rated current: 20 A.
  • Fuse dimensions: Ø56 mm × 442 mm.
  • Controlled power dissipation (CPD) design.
  • 80 N striker mechanism for switchgear operation.
  • Designed specifically for transformer short-circuit protection.

Reliable Protection for Medium Voltage Transformers

The Mersen Limitor®-PT range has been developed to protect distribution transformers from the damaging effects of high fault currents. As a back-up fuse, the L1000142 rapidly interrupts short-circuit faults while remaining coordinated with other protection devices within medium voltage electrical networks.

Its controlled power dissipation design helps maintain stable operating temperatures throughout its service life, while the integrated striker enables dependable mechanical tripping within compatible switchgear assemblies.

Typical Applications

  • Medium voltage transformer protection.
  • Electrical distribution substations.
  • Industrial power distribution systems.
  • Medium voltage switchgear.
  • Utility infrastructure.
  • Renewable energy distribution equipment.
  • Commercial and industrial electrical installations.

Technical Specifications

Voltage 240 V
Manufacturer Mersen
Series Limitor®-PT Back-up Fuses
Model L1000142
Catalogue number 45DB240V20PT
Product type High voltage DIN back-up fuse-link
Application Transformer protection
Rated voltage 24 kV AC
Rated current 20 A
Standard IEC 60282-1
Fuse diameter 56 mm
Fuse length 442 mm
Striker Controlled power dissipation, 80 N
Body material Ceramic
Fuse element Pure silver
End caps Silver-coated copper
Mounting DIN high voltage fuse mounting
EAN 3605340453157
RoHS compliant Yes
HS Code 85351000
Device Type Fuse link
Fuse Type High voltage
Current 20 A

Frequently Asked Questions

What is the Mersen L1000142 used for?

The Mersen L1000142 is a medium voltage DIN back-up fuse designed to protect transformers against high short-circuit currents.

What voltage is the L1000142 rated for?

The fuse has a rated operating voltage of 24 kV AC in accordance with IEC requirements.

What current rating does this fuse have?

The Mersen L1000142 has a 20 A current rating.

Does this fuse include a striker?

Yes. It incorporates an integrated 80 N thermal striker for use with compatible switchgear and protection systems.

Which standards does the fuse comply with?

The fuse is manufactured in accordance with IEC 60282-1 for high voltage back-up fuse-links.

Trusted by Electrical Utilities and Industry

Mersen Limitor®-PT high voltage fuse-links are trusted worldwide for dependable transformer protection, helping utilities, OEMs and industrial operators maintain reliable medium voltage electrical distribution systems.

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