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MERSEN FUSE H 1209UP BCKUP T292-56/40 W1000128
Mersen W1000128 Limitor-PT high voltage DIN transformer back-up fuse rated at 12 kV AC and 40 A, with Controlled Power Dissipation, a 63 kA breaking capacity and an integrated 80 N striker.
£76.06
Why Choose the Mersen W1000128 High Voltage DIN Back-up Fuse?
The Mersen W1000128 is a high-performance Limitor®-PT high voltage DIN back-up fuse designed to protect transformers against the damaging thermal and mechanical effects of short-circuit currents. Also identified by catalogue number 45DB120V40PT, it is intended for reliable use in medium voltage switchgear, controlgear and electrical distribution systems.
As part of the Limitor®-PT range, the W1000128 incorporates Controlled Power Dissipation (CPD) technology to support dependable long-term protection and reduce the risk of excessive thermal loading. Its pure silver fuse elements, silver-plated copper terminals and ceramic insulating body provide consistent electrical performance in demanding industrial and utility installations.
With a rated voltage of 12 kV AC, a rated current of 40 A and an integrated 80 N CPD striker, the Mersen W1000128 is suitable for transformer feeders and medium voltage protection assemblies. Its standard 56 mm diameter by 292 mm fuse-link size enables installation in compatible DIN fuse bases and switchgear systems.
Key Advantages
- Designed specifically for medium voltage transformer protection.
- 12 kV AC IEC rated voltage for high voltage distribution systems.
- 40 A rated current for compatible transformer circuits.
- Controlled Power Dissipation supports reliable long-term operation.
- Integrated 80 N striker supports indication and switchgear operation.
- 63 kA breaking capacity provides dependable short-circuit interruption.
Key Features
- Mersen Limitor®-PT series.
- Catalogue number: 45DB120V40PT.
- 12 kV AC IEC rated voltage.
- 40 A rated current.
- Controlled Power Dissipation technology.
- 80 N integrated CPD striker.
- Pure silver fuse elements with silver-plated copper terminals.
- VDE T4 design for medium voltage transformer protection.
Reliable Protection for Medium Voltage Transformers
High voltage back-up fuses protect transformers, cables and switchgear by limiting and interrupting substantial short-circuit currents before they cause serious thermal or mechanical damage. The Mersen W1000128 is engineered to remain stable during normal transformer operation while responding effectively when a high-level electrical fault occurs.
The integrated CPD striker provides fuse operation indication and can actuate a compatible switchgear mechanism. This supports coordinated circuit isolation, faster fault identification and safer maintenance within medium voltage power distribution installations.
Typical Applications
- Medium voltage distribution transformer protection.
- High voltage switchgear and controlgear.
- Electrical distribution substations.
- Ring main units and transformer feeders.
- Industrial medium voltage power systems.
- Utility and infrastructure distribution networks.
Technical Specifications
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| Fuse Indication | Striker | |
|---|---|---|
| Device Type | Fuse link | |
| Fuse Type | High voltage | |
| Current | 40 A | |
| Voltage | 12000 V | |
| Manufacturer | Mersen | |
| Series | Limitor®-PT Back-up Fuses | |
| Model | W1000128 | |
| Catalogue number | 45DB120V40PT | |
| Product type | High voltage DIN transformer back-up fuse | |
| Rated voltage | 12 kV AC | |
| Rated current | 40 A | |
| Current type | AC | |
| Breaking capacity | 63 kA | |
| Minimum interrupting rating | 125 A | |
| Clearing I²t at rated voltage | 29 kA²s | |
| Power dissipation at rated current | 54 W | |
| Fuse size | 56 mm diameter × 292 mm | |
| Overall product length | Approx. 358 mm | |
| Mounting type | Clip mounting | |
| Terminal type | Cylindrical | |
| Terminal material | Silver-plated copper | |
| Body material | Ceramic | |
| Design | VDE T4 | |
| Indication system | 80 N CPD striker | |
| Product weight | Approx. 1.6 kg | |
| Standard | IEC 60282-1 | |
| EAN | 3605340453010 | |
| HS Code | 85351000 |
Frequently Asked Questions
What is the Mersen W1000128 used for?
The W1000128 is a high voltage DIN back-up fuse designed to protect transformers and associated medium voltage equipment against damaging short-circuit currents.
What are the voltage and current ratings?
The fuse has a rated voltage of 12 kV AC and a rated current of 40 A.
What is the breaking capacity of the W1000128?
The Mersen W1000128 has a maximum AC breaking capacity of 63 kA.
What is Controlled Power Dissipation?
Controlled Power Dissipation helps manage thermal loading within the fuse and switchgear assembly, supporting reliable transformer protection and long-term operation.
Does the W1000128 include a striker?
Yes. It incorporates an integrated 80 N CPD striker for fuse operation indication and compatible switchgear tripping functions.
Trusted for Medium Voltage Transformer Protection
Mersen Limitor® high voltage fuse-links are widely used by utilities, switchgear manufacturers and industrial engineers to provide dependable transformer protection, controlled power dissipation and reliable short-circuit interruption.
