MERSEN FUSE 400V FA 0,8 A 6.32 P MI6FA40V0.8P

MERSEN FUSE 400V FA 0,8 A 6.32 P MI6FA40V0.8P

Mersen J078921 MI6FA40V0.8P high-speed semiconductor miniature fuse rated at 0.8 A and 400 V AC, featuring a 6.3 x 32 mm cartridge, clip mounting and an integrated striker.

SKU: J078921Alt SKU: MI6FA40V0.8PMPN: J078921
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Why Choose the Mersen J078921 High-Speed Miniature Fuse?

The Mersen J078921, also identified by the catalogue number MI6FA40V0.8P, is a compact high-speed semiconductor miniature fuse designed to protect sensitive electronic components against damaging overcurrents and short circuits. It forms part of Mersen’s FA range of miniature fuse-links for industrial electronics, automation equipment and power control systems.

Its high-speed operating characteristic helps interrupt excessive current rapidly, limiting the electrical energy transmitted to semiconductor devices and associated circuitry. This fast response helps reduce thermal stress and the risk of damage in applications where conventional general-purpose fuses may not operate quickly enough.

With a rated current of 0.8 A, a rated voltage of 400 V AC and a compact 6.3 × 32 mm cylindrical format, the J078921 provides dependable protection in space-restricted equipment. The fuse also includes a striker indicator, allowing its operating status to be detected visually or used with compatible signalling accessories.

Key Advantages

  • High-speed FA characteristic for semiconductor protection.
  • 0.8 A rated current for sensitive electronic circuits.
  • 400 V AC voltage rating for industrial equipment.
  • Compact 6.3 × 32 mm cylindrical cartridge format.
  • Integrated striker assists with fuse-status indication.
  • Clip-mounted design allows straightforward installation and replacement.

Key Features

  • Mersen FA semiconductor miniature fuse series.
  • Catalogue number: MI6FA40V0.8P.
  • 0.8 A rated current.
  • 400 V AC rated voltage.
  • High-speed operating characteristic.
  • Integrated striker indicator.
  • Ferrule terminals for compatible fuse clips and holders.
  • RoHS-compliant construction.

Fast Protection for Sensitive Electronic Components

Semiconductor devices can be damaged rapidly when exposed to excessive current. The Mersen J078921 uses a high-speed fuse element to disconnect the circuit quickly, helping to limit fault energy and reduce the risk of damage to protected components.

Its compact cylindrical cartridge fits compatible fuse clips and holders, allowing straightforward installation within control panels, electronic assemblies and industrial equipment. The integrated striker can provide a clear indication after the fuse has operated, helping maintenance engineers identify faults more efficiently.

Typical Applications

  • Semiconductor device protection.
  • Industrial control and automation equipment.
  • Electronic power supplies and control modules.
  • Power conversion and rectifier circuits.
  • Instrumentation and measurement equipment.
  • Industrial machinery and electronic assemblies.

Technical Specifications

Current 8 A
Voltage 400 V
Manufacturer Mersen
Product reference J078921
Catalogue number MI6FA40V0.8P
Product type High-speed semiconductor miniature fuse
Series FA / FB 400 V
Rated current 0.8 A
Rated voltage 400 V AC
Current type AC
Operating characteristic High speed FA
Fuse size 6.3 × 32 mm
Body format Cylindrical cartridge
Connection type Ferrule terminals
Mounting type Clip mounting
Indicator Striker
Compliance RoHS compliant
EAN / UPC 3605340032840
Device Type Fuse link
Fuse Type Miniature, Semiconductor
Fuse Size 6.3x32 mm

Frequently Asked Questions

What is the Mersen J078921 used for?

The Mersen J078921 provides high-speed overcurrent and short-circuit protection for sensitive semiconductor devices, electronic circuits and industrial control equipment.

What is the current rating of the J078921 fuse?

The fuse has a rated current of 0.8 A.

What voltage is the Mersen J078921 rated for?

The J078921 has a rated voltage of 400 V AC.

How is the J078921 installed?

The fuse has ferrule terminals and is designed for clip mounting in a compatible 6.3 × 32 mm fuse holder.

Does the Mersen J078921 include an indicator?

Yes. The J078921 includes a striker that can indicate when the fuse has operated and may be used with compatible signalling accessories.

Trusted Electrical Protection from Mersen

Mersen high-speed miniature fuses are used by electronic equipment manufacturers, automation engineers and maintenance professionals to provide dependable protection for sensitive semiconductor and industrial control systems.

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