MERSEN FUSE 400V SA 0,8 A 6.32 MI6SA40V0,8

MERSEN FUSE 400V SA 0,8 A 6.32 MI6SA40V0,8

Mersen W078909 MI6SA40V0.8 semiconductor miniature fuse featuring a 0.8 A current rating, 400 V AC voltage rating, medium time-lag characteristic and 6.3 x 32 mm ceramic body.

SKU: W078909Alt SKU: MI6SA40V0,8MPN: W078909
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Why Choose the Mersen W078909 High-Speed Miniature Fuse?

The Mersen W078909, catalogue number MI6SA40V0.8, is a 6.3 × 32 mm semiconductor miniature fuse designed to provide dependable overcurrent protection for sensitive electronic and semiconductor equipment. Part of Mersen's SA 400 V miniature fuse range, it features a medium time-lag characteristic that protects electronic circuits while accommodating temporary inrush currents.

With a rated current of 0.8 A and a 400 V AC voltage rating, the W078909 offers reliable protection for industrial electronics, power supplies, control equipment and semiconductor devices. Its ceramic construction and high breaking capacity ensure dependable performance in demanding electrical environments.

Designed for clip mounting, this fuse provides straightforward installation and replacement while maintaining excellent electrical performance. Its compact 6.3 × 32 mm format makes it suitable for equipment where space-saving and reliable circuit protection are essential.

Key Advantages

  • Designed for semiconductor and sensitive electronic circuit protection.
  • 0.8 A current rating for precision electronic applications.
  • 400 V AC rated voltage.
  • Medium time-lag characteristic tolerates normal inrush currents.
  • Compact 6.3 × 32 mm miniature fuse format.
  • Ceramic body provides high mechanical and thermal strength.
  • Clip mounting enables quick installation and replacement.
  • Very high breaking capacity for dependable fault interruption.

Key Features

  • Mersen SA 400 V semiconductor miniature fuse series.
  • Catalogue number: MI6SA40V0.8
  • 0.8 A rated current.
  • 400 V AC rated voltage.
  • Medium time-lag (SA) operating characteristic.
  • 6.3 × 32 mm ceramic fuse body.
  • Clip mounting installation.
  • Pre-arcing I²t: 0.17 A²s.
  • Clearing I²t: 0.38 A²s.
  • RoHS and UKCA compliant.

Reliable Protection for Electronic Equipment

The Mersen W078909 is engineered to protect semiconductor devices and electronic assemblies from damaging overcurrents. Its medium time-lag characteristic allows temporary surge currents while providing rapid fault interruption when abnormal conditions occur.

The robust ceramic body and high interrupting capability help maximise equipment reliability, making this fuse suitable for industrial automation systems, electronic controls and power conversion equipment where dependable circuit protection is critical.

Typical Applications

  • Semiconductor protection.
  • Industrial electronic equipment.
  • Power supplies and converters.
  • Automation and control panels.
  • Measurement and instrumentation systems.
  • Electronic control circuits.
  • OEM machinery.
  • Industrial power electronics.

Technical Specifications

Current 8 A
Voltage 400 V
Manufacturer Mersen
Item number W078909
Catalogue number MI6SA40V0.8
Product type Semiconductor miniature fuse
Series SA 400 V Miniature Fuses
Rated current 0.8 A
Rated voltage 400 V AC
Current type AC
Characteristic Medium time-lag (SA)
Fuse size 6.3 × 32 mm
Mounting type Clip mounting
Body material Ceramic
Pre-arcing I²t 0.17 A²s
Clearing I²t 0.38 A²s
EAN 3605340032727
Compliance RoHS, UKCA
Device Type Fuse link
Fuse Type Miniature, Semiconductor
Fuse Size 6.3x32 mm
Fuse Class Time delay

Frequently Asked Questions

What is the Mersen W078909 used for?

The W078909 is designed to protect semiconductor devices and sensitive electronic circuits from overcurrent and short-circuit faults.

What is the current rating of the W078909?

This fuse has a rated current of 0.8 A.

What voltage is the fuse rated for?

The Mersen W078909 is rated for operation at up to 400 V AC.

What type of operating characteristic does it have?

The fuse features a medium time-lag (SA) characteristic, allowing temporary inrush currents while protecting against sustained overloads.

How is the fuse installed?

The W078909 is designed for clip mounting in compatible fuse holders and equipment.

Trusted by Electrical and Automation Professionals

Mersen semiconductor miniature fuses are trusted worldwide for protecting sensitive electronic equipment, industrial control systems and power electronic applications with dependable overcurrent protection.

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