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MERSEN FUSE H 1209P BCKUP 292-56/25 E1209PIB-D1292/25
Mersen K209309 Limitor P high voltage DIN back-up fuse rated at 12 kV AC and 25 A with a standard 80 N thermal striker for transformer protection.
£64.45
Why Choose the Mersen K209309 High Voltage DIN Back-up Fuse?
The Mersen K209309 is a premium DIN high voltage back-up fuse engineered to provide reliable short-circuit protection for medium voltage transformers operating within electrical distribution systems. Part of the trusted Mersen Limitor®-P series, this fuse-link is specifically designed for transformer protection in substations, industrial switchgear and utility power networks.
Manufactured in accordance with IEC 60282-1, the K209309 delivers excellent current-limiting performance whilst helping to minimise thermal and mechanical stress during fault conditions. Premium construction using pure silver fuse elements, silver-plated copper end caps and a ceramic body ensures dependable operation and a long service life.
With a rated voltage of 12 kV AC, a 25 A current rating and an integrated 80 N thermal striker, the Mersen K209309 is ideally suited for transformer protection in medium voltage electrical installations where dependable fault interruption is essential.
Key Advantages
- Designed specifically for medium voltage transformer protection.
- 12 kV AC rated voltage for high voltage distribution systems.
- 25 A rated current for compatible transformer installations.
- Integrated 80 N thermal striker for compatible switchgear mechanisms.
- Current-limiting design reduces fault energy and equipment damage.
- Manufactured in accordance with IEC 60282-1.
Key Features
- Mersen Limitor®-P high voltage DIN back-up fuse.
- Catalogue number: 45DB120V25P.
- 12 kV AC rated voltage.
- 25 A rated current.
- 56 mm diameter × 292 mm length.
- Integrated 80 N thermal striker.
- Ceramic body with pure silver fuse elements.
- Designed for transformer protection applications.
Reliable Protection for Medium Voltage Transformers
High voltage back-up fuse-links rapidly interrupt prospective short-circuit currents before they can damage transformers and associated switchgear. Their current-limiting characteristics help reduce thermal and mechanical stress, improving equipment reliability whilst helping minimise maintenance requirements.
The Mersen Limitor®-P range has been trusted worldwide for dependable transformer protection in substations, industrial facilities and utility distribution systems, delivering consistent current-limiting performance under demanding operating conditions.
Typical Applications
- Medium voltage transformer protection.
- Electrical substations.
- Medium voltage switchgear.
- Industrial power distribution.
- Utility electrical networks.
- OEM medium voltage equipment.
Technical Specifications
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| Device Type | Fuse link | |
|---|---|---|
| Fuse Type | High voltage | |
| Current | 25 A | |
| Voltage | 12000 V | |
| Manufacturer | Mersen | |
| Series | Limitor®-P | |
| Model | K209309 | |
| Catalogue number | 45DB120V25P | |
| Product type | High voltage DIN back-up fuse | |
| Rated voltage | 12 kV AC | |
| Rated current | 25 A | |
| Frequency | 50 / 60 Hz | |
| Application | Transformer protection | |
| Fuse dimensions | Ø56 mm × 292 mm | |
| Breaking capacity | 63 kA | |
| Minimum breaking current | 93 A | |
| Clearing I²t | 5.5 kA²s | |
| Cold resistance | 52 mΩ | |
| Power dissipation at rated current | 46 W | |
| Thermal striker | Standard 80 N | |
| Body material | Ceramic | |
| Fuse element material | Pure silver | |
| End cap material | Silver-plated copper | |
| Weight | Approx. 1.7 kg | |
| EAN | 3605340218077 | |
| Standards | IEC 60282-1 | |
| RoHS compliant | Yes | |
| HS Code | 85351000 |
Frequently Asked Questions
What is the Mersen K209309 used for?
The K209309 is designed to protect medium voltage transformers against damaging short-circuit currents in electrical distribution systems.
What voltage is this fuse rated for?
The fuse has a rated operating voltage of 12 kV AC.
What is the current rating?
The Mersen K209309 has a continuous current rating of 25 A.
Does the K209309 include a thermal striker?
Yes. It incorporates a standard 80 N thermal striker for operation with compatible switchgear mechanisms.
Which standards does this fuse comply with?
The fuse is manufactured in accordance with IEC 60282-1 for high voltage transformer protection.
Trusted by Power Distribution Professionals
Mersen Limitor®-P high voltage fuse-links are trusted worldwide by utilities, transformer manufacturers and electrical engineers for dependable current-limiting protection and reliable operation in medium voltage distribution systems.
