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MERSEN FUSE 250V 5ST 4A 5.20 MI5ST25V4
Mersen Y090549 MI5ST25V4/100 time-delay 5 x 20 mm glass miniature fuse rated at 4 A and 250 V AC with a 35 A breaking capacity.
Why Choose the Mersen Y090549 5ST Time-Delay Miniature Fuse?
The Mersen Y090549, catalogue reference MI5ST25V4/100, is a dependable 5 × 20 mm time-delay miniature glass fuse designed to protect industrial equipment, electrical distribution circuits and electronic devices against overloads and short-circuit faults. Its time-delay operating characteristic allows it to withstand temporary inrush currents while providing reliable protection against sustained overcurrent conditions.
As part of the Mersen 5ST IEC Miniature Fuse series, the Y090549 is ideal for applications incorporating motors, transformers, relays and switched-mode power supplies where temporary start-up surges are expected. The transparent glass body enables quick visual inspection of the fuse element, simplifying maintenance and fault diagnosis.
With a rated current of 4 A, a rated voltage of 250 V AC and a 35 A breaking capacity, the Y090549 provides dependable circuit protection in a standard 5 × 20 mm format compatible with suitable miniature fuse holders.
Key Advantages
- Compact 5 × 20 mm miniature glass cartridge fuse.
- Time-delay characteristic withstands temporary inrush currents.
- 4 A rated current for industrial and electronic equipment.
- 250 V AC rated voltage.
- 35 A breaking capacity for dependable fault interruption.
- Transparent glass body enables quick visual inspection.
- Industry-standard dimensions simplify replacement and maintenance.
Key Features
- Mersen 5ST IEC Miniature Fuse series.
- MI5ST25V4/100 catalogue reference.
- 5 × 20 mm cylindrical glass fuse.
- 4 A nominal current rating.
- 250 V AC rated voltage.
- Time-delay operating characteristic.
- 35 A breaking capacity.
- 173.5 A²s pre-arcing I²t.
- Glass body with nickel-plated brass contact caps.
- Manufactured in accordance with IEC 60127-2.
Reliable Protection for Equipment with Inrush Currents
Time-delay miniature fuses are specifically designed to tolerate the temporary current surges produced when motors, transformers and power supplies are energised. This helps reduce nuisance fuse operation while continuing to protect equipment from prolonged overloads and short-circuit faults.
The Mersen Y090549 combines dependable electrical performance with an industry-standard 5 × 20 mm format, making it suitable for industrial automation, instrumentation, OEM machinery and electrical control systems requiring reliable replaceable circuit protection.
Typical Applications
- Industrial control panels.
- Motor control circuits.
- Transformer protection.
- Power supplies.
- Electronic equipment.
- Instrumentation and measurement systems.
- OEM machinery.
- General industrial electrical installations.
Technical Specifications
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| Current | 4 A | |
|---|---|---|
| Voltage | 250 V | |
| Device Type | Fuse link | |
| Fuse Type | Miniature | |
| Fuse Size | 5x20 mm | |
| Fuse Class | Time delay | |
| Manufacturer | Mersen | |
| Series | IEC Miniature Fuses 5 × 20 - Time-lag - 5ST | |
| Item number | Y090549 | |
| Catalogue number | MI5ST25V4/100 | |
| Product type | Time-delay miniature glass fuse | |
| Fuse size | 5 × 20 mm | |
| Rated current | 4 A | |
| Rated voltage | 250 V AC | |
| Operating characteristic | Time-delay | |
| Breaking capacity | 35 A | |
| Pre-arcing I²t | 173.5 A²s | |
| Power loss at rated current | 0.64 W | |
| Maximum voltage drop | 0.06 V | |
| Body material | Glass | |
| Contact cap material | Nickel-plated brass | |
| Applicable standard | IEC 60127-2 | |
| EAN | 3605340091984 | |
| RoHS compliant | Yes |
Frequently Asked Questions
What is the Mersen Y090549 used for?
The Mersen Y090549 protects industrial and electronic equipment against overloads and short circuits while allowing temporary start-up current surges.
What is the current rating of the Y090549?
The fuse has a nominal current rating of 4 A.
Is the Y090549 fast-acting or time-delay?
The Y090549 is a time-delay fuse designed for circuits with temporary inrush currents.
What fuse holder is compatible?
The fuse should be installed in a compatible 5 × 20 mm miniature fuse holder with suitable electrical ratings.
What is the breaking capacity of the Y090549?
The Mersen Y090549 has a rated AC breaking capacity of 35 A, providing dependable interruption of overload and fault currents.
Trusted Circuit Protection from Mersen
Mersen miniature fuses are trusted worldwide by electrical engineers, machine builders and equipment manufacturers to deliver dependable overcurrent protection across industrial, commercial and electronic applications.
