Littelfuse 279.125 - 279S VERY FAST ACTING MICRO FUSE .125A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
Littelfuse

279.125

Alternate Item Number: 0279.125V

UPC: 079458105070


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Minimum Qty: 5

Multiplier: 5

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Overview

The Littelfuse 279.125 MICRO fuse is a very fast-acting, 0.125A plug-in fuse designed for critical circuit protection in compact electronic and industrial applications. Originally engineered for the U.S. Space Program, this MICRO series fuse delivers exceptional reliability and performance in a miniature form factor. With a current rating of 0.125A, it is ideal for protecting sensitive components from overcurrent conditions where space is at a premium. Key specifications include a plug-in mounting style for easy installation and replacement, minimizing downtime in production environments. The fuse offers a high breaking capacity, ensuring robust protection against transient overcurrents. A clear cover option is available for visual inspection of the fuse element status, simplifying maintenance and troubleshooting. Military-grade variants are offered for harsh or demanding environments, maintaining performance under extreme conditions. The MICRO series spans ampere ratings from 2mA to 5A, providing flexibility for diverse design requirements. The 279.125 model is part of this trusted line, combining proven space-grade reliability with modern manufacturing standards. Its compact design allows efficient use of PCB real estate, making it suitable for densely populated circuits in aerospace, defense, telecommunications, and industrial control systems. The plug-in design with short or long leads options further enhances installation flexibility. Choose the Littelfuse 279.125 for applications requiring fast-acting, space-efficient overcurrent protection with a heritage of reliability. This fuse is a direct drop-in solution for engineers prioritizing both performance and footprint optimization in their designs.
  • Very fast-acting fuse with 0.125A current rating
  • Plug-in mounting style for easy installation and replacement
  • High breaking capacity for robust overcurrent protection
  • Clear cover option for visual inspection of fuse element status
  • Military-grade variants available for harsh environments
  • Military-grade variants available for harsh environments
  • Compact design for space-constrained PCB layouts
  • Part of Littelfuse MICRO series (2mA to 5A range)

Specifications

Application
electronic equipment & appliances
Brand Name
Littelfuse
Connection Type
Plug-in
Current Rating
0.125 A
Mounting Type
Plug-in
Series
MICRO
Size
Compact/MICRO
Special Features
High breaking capacity
Standard
CSA Approval
Sub Brand
279 Series
Type
Plug In
279S VERY FAST ACTING MICRO FUSE .100A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

279.100

279S VERY FAST ACTING MICRO FUSE .100A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
279S VERY FAST ACTING MICRO FUSE .062A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

279.062

279S VERY FAST ACTING MICRO FUSE .062A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
278S VERY FAST ACTING MICRO FUSE .062A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.062

278S VERY FAST ACTING MICRO FUSE .062A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
279S VERY FAST ACTING MICRO FUSE .050A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

279.050

279S VERY FAST ACTING MICRO FUSE .050A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
278S VERY FAST ACTING MICRO FUSE .050A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.050

278S VERY FAST ACTING MICRO FUSE .050A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
278S VERY FAST ACTING MICRO FUSE .200A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.200

278S VERY FAST ACTING MICRO FUSE .200A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
278S VERY FAST ACTING MICRO FUSE .300A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.300

278S VERY FAST ACTING MICRO FUSE .300A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
278S VERY FAST ACTING MICRO FUSE .031A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.031

278S VERY FAST ACTING MICRO FUSE .031A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
278S VERY FAST ACTING MICRO FUSE .015A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.015

278S VERY FAST ACTING MICRO FUSE .015A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
FUSE 125V FM02A MIL MICRO FUSE .015A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 0.002A to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 0.002A to 5A. Plug-in with short or long leads option. Applications: Printed circuit boards and similar equipment. Electronic components.

274.015

FUSE 125V FM02A MIL MICRO FUSE .015A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 0.002A to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 0.002A to 5A. Plug-in with short or long leads option. Applications: Printed circuit boards and similar equipment. Electronic components.
278S VERY FAST ACTING MICRO FUSE .010A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

278.010

278S VERY FAST ACTING MICRO FUSE .010A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.
279S VERY FAST ACTING MICRO FUSE .005A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

279.005

279S VERY FAST ACTING MICRO FUSE .005A. Developed originally for the U.S. Space Program, MICRO™ fuse provides reliability in a compact design. The MICRO™ fuse is available in plug–in or radial lead styles and a complete range of ampere ratings from 1/500 to 5A to suit a wide variety of design needs. Features: Military grade available. High breaking capacity. Clear cover option to view fuse element status. Available from very low ampere of 2mA to 5A Plug-in with short or long leads option.

Frequently Asked Questions about Littelfuse

What certifications and standards do Littelfuse products comply with?

Littelfuse products are certified to multiple international standards, including UL (Underwriters Laboratories), CSA (Canadian Standards Association), CCC (China Compulsory Certification), and EAC (Eurasian Conformity). Customers can verify specific product certifications by consulting individual product datasheets on Littelfuse.com, which provide comprehensive details about standards compliance for each component.

What industries and applications are Littelfuse products used for?

Littelfuse products are critical for electrical protection and safety across multiple industrial sectors, including manufacturing, automation, power distribution, and electrical control systems. Their comprehensive product portfolio serves industries that require robust electrical protection, including motor and pump applications, solar installations, programmable logic controllers (PLCs), electrical switch panels, and critical infrastructure environments. Key product lines protect against overcurrent, voltage transients, ground faults, and temperature-related electrical risks, ensuring equipment safety and operational reliability.

What technical support does Littelfuse offer?

Littelfuse offers comprehensive technical support through multiple channels. Their Technical Hotline (800-TEC-FUSE) provides direct access to engineers who can help identify issues and recommend solutions. Additionally, Littelfuse offers extensive online Technical Resources at Littelfuse.com, including datasheets, product manuals, whitepapers, application guides, and online design tools. Their experienced product and application engineers also provide step-by-step support from design to installation.

What are the main product lines offered by Littelfuse?

Littelfuse offers comprehensive industrial protection and control product lines, including fuses, fuse holders, protection relays, temperature sensors, and electrical safety components. Their key product categories span surge protective devices, custom OEM products, electrical switch panels, medium voltage fuses, ground-fault protection relays, motor and pump protection devices, and temperature sensors. These products are designed to minimize electrical safety hazards, limit equipment damage, improve productivity, and safeguard personnel from electrical faults.

What are the key features of Littelfuse products?

Littelfuse products feature exceptional circuit protection technologies with key characteristics including UL/IEC safety standard compliance, low internal resistance, and advanced protective capabilities across multiple product lines. Their components provide critical protection for industrial systems, offering features like overcurrent protection, voltage transient suppression, and resettable protection devices with ultra-low resistance and compact designs. Key product lines include fuses, metal oxide varistors (MOVs), TVS diodes, PolySwitch devices, and specialized electronic protection components that enhance system reliability and safety.

What environmental ratings do Littelfuse products have?

Littelfuse products feature comprehensive environmental ratings, including NEMA Type 1, 2, 3, 3R, 4/4X, 12, and 13 certifications, as well as IP65 protection. These ratings ensure superior protection in diverse industrial environments, with an operating temperature range of -40°F to +131°F (-40°C to +55°C). Many products also include UV-stabilized materials and neoprene gaskets for enhanced durability in outdoor and challenging conditions.

What accessories are available for Littelfuse products?

Littelfuse offers several key accessories across their product lines, including fuse holders, voltage monitoring modules, and terminal connectors. Specific accessories include the LPSM003ZXID (indicating) and LPSM003Z (non-indicating) POWR-SAFE Dead Front fuse holders for Class CC and Midget-Style fuses, the VRM6048 voltage monitor accessory module, and female quick connect terminals (P1015 series) in various wire gauge sizes. These accessories are designed to enhance protection, monitoring, and connectivity for Littelfuse electrical components.

What is Littelfuse's warranty policy?

Littelfuse provides comprehensive warranty details on their official website at www.littelfuse.com/warranty. Customers should visit this page to review the specific warranty terms and conditions for their specific product lines. For direct warranty support or questions, customers can contact Littelfuse Technical Support at 1-800-TEC-FUSE or email [email protected].

What communication protocols do Littelfuse products support?

Littelfuse supports a comprehensive range of industrial communication protocols, including PROFIBUS, PROFINET, EtherNet/IP, DeviceNet, Modbus RTU, and CANopen. Our products provide flexible connectivity solutions across multiple industrial automation platforms, enabling seamless integration with various control systems and network architectures.

How are Littelfuse products typically installed?

Littelfuse products are typically installed using specialized mounting hardware like fuse holders, blocks, and panels designed for specific industrial applications. The POWR-SAFE Dead Front holders, for example, provide optimum protection for Class CC and Midget-Style fuses, supporting installations up to 600 VAC/DC. Installation often involves using precision terminals with strain relief, such as 0.25 in. female quick connect terminals, to ensure secure and safe electrical connections in industrial control systems.