Why Choose the Mersen A1000109 High-Voltage Transformer Fuse?
The Mersen A1000109, catalogue number 45DB240V1P, is a high-performance DIN high-voltage back-up fuse developed for the protection of transformers against damaging short-circuit currents. Part of the established Mersen Limitor®-P series, it is designed for dependable use in high-voltage switchgear, controlgear and electrical distribution systems.
Rated at 24 kV AC and 1 A, the A1000109 provides current-limiting protection for sensitive transformer circuits. Its rapid fault-clearing performance helps reduce the peak current, thermal energy and mechanical stress imposed on transformers and associated high-voltage equipment during a short circuit.
The fuse features a robust ceramic body, pure silver fuse elements and silver-coated copper end caps for reliable electrical performance. Measuring approximately 56 × 442 mm, it also incorporates a standard 80 N medium striker for fuse-operation indication and actuation of compatible switchgear mechanisms.
Key Advantages
- Designed specifically for high-voltage transformer protection.
- 24 kV AC rated voltage for medium-voltage distribution systems.
- 1 A rated current for sensitive transformer circuits.
- High current limitation helps reduce short-circuit energy.
- Fast fault interruption protects transformers and switchgear.
- Integrated 80 N striker for indication and mechanical actuation.
- Suitable for indoor and outdoor high-voltage equipment.
- Robust ceramic construction for dependable service life.
Key Features
- Mersen Limitor®-P high-voltage back-up fuse.
- Manufacturer part number: A1000109.
- Catalogue number: 45DB240V1P.
- Rated voltage: 24 kV AC.
- Rated current: 1 A.
- Fuse diameter: Approximately 56 mm.
- Fuse length: Approximately 442 mm.
- Striker type: Standard medium striker.
- Striker force: 80 N.
- DIN-format fuse-link for compatible high-voltage fusegear.
The Mersen A1000109 is a back-up fuse designed to interrupt high short-circuit currents in transformer circuits. Its current-limiting action restricts the peak fault current before it reaches its full prospective value, helping protect transformer windings, cables and high-voltage switchgear from severe electrical and mechanical damage.
As a back-up fuse, the A1000109 must be coordinated with suitable switching and protective equipment to cover the complete required current range. Correct fuse selection should consider the transformer rating, system voltage, inrush current and the requirements of the associated switchgear.
Typical Applications
- High-voltage distribution transformer protection.
- Medium-voltage switchgear and controlgear.
- Transformer substations.
- Industrial power distribution systems.
- Utility and infrastructure installations.
- Indoor and outdoor high-voltage equipment.
- Fuse-switch combinations for transformer circuits.
