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MERSEN FUSE H 1209UP BCKUP T292-56/20 45DB120V20PT
Mersen S1000125 Limitor-PT DIN high voltage back-up fuse-link with controlled power dissipation for transformer protection. Rated 12 kV AC and 20 A.
£66.81
Why Choose the Mersen S1000125 High Voltage Transformer Fuse?
The Mersen S1000125 is a premium DIN high voltage back-up fuse-link designed to protect transformers and medium voltage electrical equipment against damaging short-circuit currents. As part of the trusted Mersen Limitor®-PT series, it features controlled power dissipation (CPD), making it particularly suitable for modern compact switchgear installations where reduced heat generation is essential.
Designed in accordance with IEC 60282-1, the S1000125 provides dependable transformer protection while reducing power losses inside enclosed switchgear. Manufactured using pure silver fuse elements, silver-coated copper contact caps and a robust ceramic body, it delivers reliable interruption performance and long operational life in demanding industrial and utility environments.
With a rated voltage of 12 kV AC and a rated current of 20 A, the Mersen S1000125 is ideal for medium voltage transformer protection. Its 56 mm diameter, 292 mm fuse length and integrated 80 N striker allow straightforward installation into compatible DIN fuse bases and switchgear.
Key Advantages
- Designed specifically for medium voltage transformer protection.
- 12 kV AC rated voltage for industrial and utility networks.
- 20 A rated current.
- Controlled power dissipation reduces heat build-up inside switchgear.
- Integrated 80 N striker for compatible switchgear tripping.
- Current-limiting operation minimises damaging fault energy.
- Pure silver fuse elements provide dependable interruption.
- Manufactured in accordance with IEC 60282-1.
Key Features
- Mersen Limitor®-PT back-up fuse series.
- Catalogue number: 45DB120V20PT.
- 12 kV AC rated voltage.
- 20 A rated current.
- 56 mm fuse diameter.
- 292 mm fuse length.
- Integrated 80 N striker.
- Controlled power dissipation (CPD).
- Pure silver fuse elements.
- Silver-coated copper contact caps.
- High-strength ceramic body.
Reliable Protection for Medium Voltage Transformers
The Mersen S1000125 rapidly interrupts high prospective short-circuit currents before excessive thermal or mechanical stress can damage transformers, switchgear or associated electrical equipment. Its controlled power dissipation design helps reduce internal switchgear temperatures while maintaining dependable protection.
As a high voltage back-up fuse-link, the S1000125 is intended for coordinated transformer protection and should be used alongside suitable overload protection. The integrated striker enables compatible switchgear trip mechanisms or indication systems to operate whenever the fuse interrupts a fault.
Typical Applications
- Medium voltage transformer protection.
- Industrial switchgear.
- Utility substations.
- Power distribution systems.
- Renewable energy installations.
- Manufacturing facilities.
- Commercial infrastructure.
- OEM medium voltage equipment.
Technical Specifications
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| Voltage | 120 V | |
|---|---|---|
| Device Type | Fuse link | |
| Fuse Type | High voltage | |
| Current | 20 A | |
| Manufacturer | Mersen | |
| Series | Limitor®-PT Back-up Fuses with Controlled Power Dissipation | |
| Model | S1000125 | |
| Catalogue number | 45DB120V20PT | |
| Product type | DIN high voltage back-up fuse-link | |
| Primary application | Transformer protection | |
| Rated voltage | 12 kV AC | |
| Rated current | 20 A | |
| Breaking capacity | 63 kA | |
| Clearing I²t | 3.7 kA²s | |
| Minimum breaking current | 73 A | |
| Cold resistance | 71 mΩ | |
| Power dissipation at rated current | 38 W | |
| Fuse diameter | 56 mm | |
| Fuse length | 292 mm | |
| Striker | 80 N | |
| Fuse element material | Pure silver | |
| Contact cap material | Silver-coated copper | |
| Body material | Ceramic | |
| Weight | Approx. 1.6 kg | |
| Frequency | 50 / 60 Hz | |
| Applicable standard | IEC 60282-1 | |
| EAN / UPC | 3605340452983 | |
| RoHS compliant | Yes | |
| HS Code | 85351000 |
Frequently Asked Questions
What is the Mersen S1000125 used for?
The Mersen S1000125 is a DIN high voltage back-up fuse-link designed to protect medium voltage transformers against damaging short-circuit currents.
What are the voltage and current ratings?
This fuse-link is rated at 12 kV AC with a continuous current rating of 20 A.
What does controlled power dissipation mean?
Controlled power dissipation helps reduce heat generated inside switchgear, improving thermal performance while maintaining reliable transformer protection.
Does the S1000125 include a striker?
Yes. It incorporates a standard 80 N striker for operation of compatible switchgear tripping or indication mechanisms.
What are the physical dimensions?
The fuse-link measures 56 mm in diameter and 292 mm in length.
Trusted by Power Distribution Engineers Worldwide
Mersen Limitor®-PT high voltage fuse-links are trusted by utilities, switchgear manufacturers and industrial engineers worldwide for dependable transformer protection, controlled power dissipation and reliable medium voltage fault interruption.
