MERSEN FUSE 250V 5ST 12,5A 5X20 MI5ST25V12,5

MERSEN FUSE 250V 5ST 12,5A 5X20 MI5ST25V12,5

Mersen Z233449 MI5ST25V12.5 time-delay glass miniature cartridge fuse rated at 12.5 A and 250 V AC, supplied in a standard 5 x 20 mm format for industrial circuit protection.

SKU: Z233449Alt SKU: MI5ST25V12.5MPN: Z233449
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Why Choose the Mersen Z233449 MI5ST25V12.5 Miniature Fuse?

The Mersen Z233449 MI5ST25V12.5 is a dependable time-delay miniature cartridge fuse designed to protect industrial equipment, control circuits and electrical assemblies against sustained overloads and short circuits. Part of the established Mersen 5ST IEC miniature fuse range, it is suitable for equipment that experiences temporary inrush currents during normal start-up.

Manufactured in the standard 5 × 20 mm glass cartridge format, the Z233449 can be installed in compatible miniature fuse holders and fuse clips. Its transparent glass body allows the internal fuse element to be inspected visually, supporting efficient fault diagnosis and routine electrical maintenance.

With a rated current of 12.5 A and a rated voltage of 250 V AC, this fuse is suitable for power supplies, transformers, control panels and industrial machinery. Its time-delay characteristic helps prevent nuisance operation caused by brief start-up surges while maintaining reliable protection against prolonged overcurrent conditions.

Key Advantages

  • Time-delay operation withstands temporary start-up and inrush currents.
  • 12.5 A current rating for industrial and electrical equipment.
  • 250 V AC rated voltage for low-voltage circuit protection.
  • Standard 5 × 20 mm miniature cartridge format.
  • Transparent glass body allows convenient visual inspection.
  • Reliable Mersen construction for maintenance and OEM applications.

Key Features

  • Mersen MI5ST25V12.5 miniature cartridge fuse.
  • 12.5 A rated current.
  • 250 V AC rated voltage.
  • Time-delay fuse characteristic.
  • Standard 5 × 20 mm cartridge dimensions.
  • Glass body with cylindrical metal end caps.
  • Suitable for circuits with temporary inrush currents.
  • Designed for installation in compatible fuse holders or fuse clips.

Time-Delay Protection for Electrical Equipment

Time-delay cartridge fuses are designed to tolerate brief current surges that occur when transformers, power supplies, motors and other inductive loads are energised. This allows normal start-up currents to pass without unnecessary fuse operation while maintaining protection against sustained overloads and short circuits.

The Mersen Z233449 combines a 12.5 A rating with compact 5 × 20 mm dimensions, making it suitable for original equipment and replacement applications. The current rating, voltage rating, operating characteristic and required breaking capacity should always be checked against the protected equipment before installation.

Typical Applications

  • Industrial control panels.
  • Power supplies and power conversion equipment.
  • Transformers and inductive loads.
  • Industrial machinery and automation systems.
  • Instrumentation and monitoring equipment.
  • OEM electrical and electronic assemblies.

Technical Specifications

Current 5 A
Voltage 250 V
Manufacturer Mersen
Series 5ST IEC Miniature Fuses
Model MI5ST25V12.5
Part number Z233449
Product type Miniature cartridge fuse
Fuse characteristic Time delay
Rated current 12.5 A
Rated voltage 250 V AC
Fuse size 5 × 20 mm
Body material Glass
Terminal type Cylindrical metal end caps
Mounting Compatible fuse holder or fuse clip
Country of origin Germany
Application Electrical equipment and industrial circuit protection
Device Type Fuse link
Fuse Type Miniature
Fuse Size 5x20 mm
Fuse Class Time delay

Frequently Asked Questions

What is the Mersen Z233449 used for?

The Mersen Z233449 provides time-delay overcurrent protection for industrial equipment, power supplies, control circuits and electrical assemblies that may experience temporary inrush currents.

What is the current rating of the Z233449?

The fuse has a rated current of 12.5 A.

What voltage is this fuse rated for?

The Mersen Z233449 is rated for circuits operating at up to 250 V AC.

What size is the Mersen Z233449 fuse?

It uses the standard 5 × 20 mm miniature cartridge fuse format.

What does the time-delay characteristic mean?

The time-delay characteristic allows the fuse to withstand brief start-up or inrush currents while still interrupting sustained overloads and short circuits.

Trusted by Electrical Professionals Worldwide

Mersen miniature cartridge fuses are widely used by panel builders, maintenance engineers and OEM manufacturers to provide dependable circuit protection across industrial and commercial electrical installations.

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