MERSEN FUSE 250V FA 1,25A 5.20 AL MI5FAP25V1,25

MERSEN FUSE 250V FA 1,25A 5.20 AL MI5FAP25V1,25

Mersen R208257 high-speed 5 x 20 mm miniature fuse with a 1.25 A current rating, 250 V AC voltage rating, FA operating characteristic and axial lead mounting.

SKU: R208257Alt SKU: MI5FAP25V1,25MPN: R208257
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List Price £3.48 ex VAT
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Why Choose the Mersen R208257 High-Speed Miniature Fuse?

The Mersen R208257 is a compact high-speed miniature fuse designed to provide rapid overcurrent and short-circuit protection for sensitive electronic components and semiconductor devices. As part of the Mersen MI5 FA/FB 250V AL series, it delivers very fast fault interruption in a space-saving format suitable for modern electronic and industrial equipment.

With a rated current of 1.25 A and a rated voltage of 250 V AC, the R208257 helps limit the damaging electrical energy passed to protected components during a fault. Its high-speed FA operating characteristic makes it particularly suitable for circuits containing semiconductors and other components that can be damaged by relatively short overcurrent events.

The fuse features a compact 5 × 20 mm body and axial leads that allow direct soldering onto printed circuit boards or connection within electronic assemblies. Its combination of rapid operation, compact dimensions and dependable performance makes it suitable for industrial controls, power electronics, instrumentation and automation equipment.

Key Advantages

  • High-speed FA characteristic for rapid fault interruption.
  • 1.25 A current rating for sensitive electronic circuits.
  • 250 V AC rated voltage for industrial and electronic applications.
  • Compact 5 × 20 mm miniature fuse format.
  • Axial leads support direct PCB mounting and soldered installation.
  • Very high breaking capacity helps protect equipment from damaging fault currents.

Key Features

  • Mersen MI5 FA/FB 250V AL series.
  • 1.25 A rated current.
  • 250 V AC IEC rated voltage.
  • High-speed FA operating characteristic.
  • Compact 5 × 20 mm fuse body.
  • Axial leads for direct soldering and component integration.
  • Designed for semiconductor and sensitive electronic circuit protection.
  • Suitable for AC electrical circuits.

Rapid Protection for Sensitive Electronic Components

High-speed fuses are engineered to interrupt fault currents more quickly than conventional general-purpose fuses. This rapid response helps reduce the amount of electrical energy reaching semiconductor devices, electronic components and control circuits during an overload or short circuit.

The Mersen R208257 combines high-speed protection with axial lead mounting, making it straightforward to integrate into printed circuit boards and electronic assemblies. Its compact format is ideal for applications where installation space is limited but reliable fault protection remains essential.

Typical Applications

  • Semiconductor protection circuits.
  • Industrial control equipment.
  • Electronic power supplies.
  • Power conversion equipment.
  • Instrumentation and test systems.
  • Printed circuit board assemblies.

Technical Specifications

Current 25 A
Voltage 250 V
Manufacturer Mersen
Series MI5 FA/FB 250V AL
Model R208257
Catalogue number MI5FAP25V1.25
Product type High-speed miniature fuse
Rated current 1.25 A
Rated voltage 250 V AC
Operating characteristic High-speed FA
Fuse size 5 × 20 mm
Mounting type Axial leads
Current type AC
Application Semiconductor and electronic circuit protection
EAN / UPC 3605340209051
Device Type Fuse link
Fuse Type Miniature, Semiconductor
Fuse Size 5x20 mm

Frequently Asked Questions

What is the Mersen R208257 used for?

The R208257 is used to protect sensitive electronic components and semiconductor devices against overloads and short circuits.

What is the current rating of the Mersen R208257?

The fuse has a rated current of 1.25 A.

What voltage is this fuse rated for?

The Mersen R208257 has a rated voltage of 250 V AC.

Is the R208257 a high-speed fuse?

Yes. It has a high-speed FA characteristic designed to provide rapid protection for semiconductor devices and sensitive electronic circuits.

How is the Mersen R208257 installed?

The fuse has axial leads that allow it to be soldered directly onto a printed circuit board or connected within an electronic assembly.

Trusted by Electronics and Automation Engineers

Mersen high-speed miniature fuses are trusted by equipment manufacturers and industrial engineers for dependable protection of semiconductor devices, power electronics and sensitive control circuits.

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