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MERSEN FUSE 250V 5ST 0,4A 5.20 MI5ST25V0,4
Mersen M090539 MI5ST25V0.4 5 x 20 mm time-delay glass cartridge fuse rated at 0.4 A and 250 V AC for electrical distribution and industrial equipment protection.
Why Choose the Mersen M090539 5 x 20 mm Time-Delay Glass Cartridge Fuse?
The Mersen M090539, manufacturer reference MI5ST25V0.4, is a compact 5 x 20 mm time-delay glass cartridge fuse designed to provide dependable overcurrent protection for electrical distribution circuits, industrial control equipment and electronic systems. Rated at 0.4 A and 250 V AC, it protects wiring and components against sustained overloads and short-circuit conditions.
As part of the established Mersen 5ST IEC miniature fuse series, the M090539 features a time-delay operating characteristic that withstands brief, high inrush currents without opening unnecessarily. This makes it particularly suitable for circuits containing small motors, transformers, power supplies and other equipment that draws a temporary surge when energised.
The fuse has a transparent glass body and standard 5 x 20 mm dimensions, allowing straightforward visual inspection and installation in compatible fuse clips, bases and enclosed holders. Its combination of compact construction, defined electrical performance and Mersen manufacturing quality makes it a reliable choice for OEM assembly, panel building and maintenance applications.
Key Advantages
- Compact 5 x 20 mm time-delay cartridge fuse.
- 0.4 A current rating for low-current circuit protection.
- 250 V AC voltage rating for industrial and electronic equipment.
- Time-delay response withstands brief start-up and inrush currents.
- Transparent glass body supports quick visual inspection.
- Standard cartridge dimensions simplify installation and replacement.
Key Features
- Mersen 5ST IEC miniature fuse series.
- Manufacturer reference: MI5ST25V0.4.
- Rated current: 0.4 A / 400 mA.
- Rated voltage: 250 V AC.
- Fuse characteristic: Time-delay.
- Fuse size: 5 x 20 mm.
- Glass cartridge body for visual condition checking.
- Suitable for compatible miniature fuse holders and clips.
- Designed for industrial electrical and electronic applications.
Reliable Time-Delay Circuit Protection
Time-delay fuses are designed to tolerate short-duration current peaks that occur during the normal start-up of motors, transformers and capacitive power supplies. Unlike a quick-acting fuse, the Mersen M090539 does not open immediately during an acceptable temporary surge, helping prevent unnecessary equipment downtime and repeated fuse replacement.
When an overload continues beyond the permitted time-current profile, or a short circuit develops, the fuse interrupts the circuit to help protect connected equipment and conductors. The M090539 is therefore well suited to installations requiring both inrush tolerance and dependable fault protection.
Typical Applications
- Industrial control panels.
- Electrical distribution circuits.
- Small motor control equipment.
- Control transformers.
- Power supplies and electronic equipment.
- Automation and instrumentation systems.
- OEM electrical assemblies.
- Maintenance and replacement applications.
Technical Specifications
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| Current | 0.4 A | |
|---|---|---|
| Voltage | 250 V | |
| Device Type | Fuse link | |
| Fuse Type | Miniature | |
| Fuse Size | 5x20 mm | |
| Fuse Class | Time delay | |
| Manufacturer | Mersen | |
| Series | 5ST IEC Miniature Fuses | |
| Model | M090539 | |
| Manufacturer reference | MI5ST25V0.4 | |
| Product type | Time-delay miniature cartridge fuse | |
| Rated current | 0.4 A / 400 mA | |
| Rated voltage | 250 V AC | |
| Current type | AC | |
| Fuse speed | Time-delay | |
| Fuse characteristic | T | |
| Fuse size | 5 x 20 mm | |
| Overall length | 20 mm | |
| Diameter | Approximately 5 mm | |
| Body material | Glass | |
| Mounting method | Compatible fuse clip or holder | |
| Application | Electrical distribution and industrial equipment protection | |
| RoHS compliant | Yes |
Frequently Asked Questions
What is the Mersen M090539 used for?
The Mersen M090539 protects electrical distribution circuits, industrial control equipment and electronic systems against sustained overloads and short circuits.
What are the current and voltage ratings?
The fuse is rated at 0.4 A, or 400 mA, with a maximum rated voltage of 250 V AC.
What does time-delay mean?
A time-delay fuse tolerates brief start-up or inrush currents without opening unnecessarily, while still disconnecting the circuit during a sustained overcurrent.
What size is the Mersen M090539?
It is a standard 5 x 20 mm miniature glass cartridge fuse for installation in compatible fuse holders and clips.
Can this fuse be used in motor and transformer circuits?
Its time-delay characteristic makes it suitable for many small motor and transformer applications that experience temporary starting currents, provided the circuit voltage, current and fault ratings are compatible.
Trusted by Electrical Professionals Worldwide
Mersen miniature fuses are specified by panel builders, equipment manufacturers and maintenance engineers for reliable overcurrent protection across industrial electrical and electronic systems.
