Why Choose the Mersen S079021 Miniature Fuse?
The Mersen S079021 is a compact and dependable medium time-lag miniature fuse designed to protect industrial controls, electrical equipment and electronic circuits against overloads and short circuits. Identified by the catalogue number MI5M25V4P, this fuse combines reliable fault protection with the ability to tolerate temporary current surges during normal equipment operation.
With a rated current of 4 A and a rated voltage of 250 V AC, the S079021 is suitable for circuits containing transformers, relays, control components and other devices that may draw brief inrush currents. Its medium time-lag operating characteristic helps prevent unnecessary fuse operation while still providing effective protection against sustained overcurrent conditions.
The fuse features a compact 5.2 × 25 mm ceramic body and an integrated striker indicator. This design provides a clear mechanical indication when the fuse has operated and can support auxiliary signalling or monitoring arrangements in compatible equipment.
Key Advantages
- Medium time-lag characteristic withstands temporary current surges.
- 4 A rated current for industrial and electronic circuits.
- 250 V AC rated voltage for low-voltage equipment protection.
- Compact 5.2 × 25 mm miniature fuse format.
- Integrated striker provides a visible mechanical indication after operation.
- Ceramic construction supports dependable fault interruption.
Key Features
- Mersen MI5M miniature fuse range.
- 4 A nominal current rating.
- 250 V AC rated voltage.
- Medium time-lag operating characteristic.
- Integrated striker or indicator feature.
- Compact ceramic cylindrical body.
- Suitable for compatible inline holders and fuse carriers.
- Designed for industrial electrical distribution and control circuits.
Dependable Protection for Circuits with Inrush Current
Medium time-lag fuses are designed to tolerate brief current peaks that can occur when transformers, motors, relays and power supplies are energised. This helps reduce nuisance operation without compromising protection against prolonged overloads or short circuits.
The Mersen S079021 also incorporates a striker mechanism that provides a mechanical indication when the fuse element has operated. In compatible equipment, this feature can assist with fault identification, status monitoring and maintenance.
Typical Applications
- Industrial control panels.
- Transformer protection circuits.
- Relays and contactor control systems.
- Electronic power supplies.
- Electrical distribution equipment.
- Automation and monitoring systems.