Littelfuse H273003 - 273S VERY FAST ACTING MICRO H-PACK 3A. 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

H273003

Alternate Item Number: 0273003.H

UPC: 079458873054


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Minimum Qty: 100

Multiplier: 100

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Overview

The Littelfuse 273S 3A Very Fast Acting Micro H-Pack Fuse (SKU: H273003) represents a pinnacle of miniaturized circuit protection, originally engineered for the demanding requirements of the U.S. Space Program. This exceptional fuse delivers unparalleled reliability in a compact H-Pack design, making it an indispensable component for critical applications where space is at a premium and performance cannot be compromised. Its very fast-acting characteristic ensures rapid interruption of fault currents, safeguarding sensitive electronic equipment from damage and preventing cascading failures. The MICRO™ fuse series, to which the 273S model belongs, is renowned for its robust construction and high breaking capacity, capable of withstanding significant overcurrent events. Available in both plug-in and radial lead styles, this fuse offers remarkable design flexibility, allowing engineers to seamlessly integrate it into a wide array of electronic assemblies. The plug-in option further provides choices for short or long leads, catering to diverse mounting and connectivity needs. This versatility is crucial for custom designs and retrofitting existing systems. With a comprehensive range of ampere ratings spanning from a minuscule 2mA up to 5A, the MICRO™ fuse series can be precisely specified for virtually any protection requirement. The 3A rating of the H273003 model makes it particularly suitable for medium-power circuits in industrial control systems, telecommunications equipment, medical devices, and advanced aerospace and defense electronics. The availability of military-grade options underscores its suitability for the most stringent environments and performance standards. Key features that distinguish the Littelfuse 273S include: * **Exceptional Reliability:** Developed for space applications, ensuring utmost dependability. * **Very Fast Acting:** Provides rapid response to overcurrents, minimizing damage. * **Compact H-Pack Design:** Ideal for space-constrained applications. * **Versatile Mounting Options:** Available in plug-in (with short/long leads) and radial lead styles. * **Wide Ampere Range:** From 2mA to 5A, offering precise protection. * **High Breaking Capacity:** Withstands significant fault currents. * **Military Grade Availability:** Meets rigorous defense and aerospace standards. * **Clear Cover Option:** Allows for visual inspection of the fuse element status, simplifying troubleshooting and maintenance. Professionals in the industrial, aerospace, and defense sectors trust Littelfuse for their critical protection needs. The company's long-standing reputation for quality and innovation is evident in the meticulous engineering of the MICRO™ fuse series. When selecting a fuse for applications demanding unwavering performance, precise protection, and long-term reliability, the Littelfuse 273S 3A Very Fast Acting Micro H-Pack Fuse is an exemplary choice, ensuring the integrity and longevity of your valuable electronic systems.
  • Littelfuse 273S 3A Very Fast Acting Micro H-Pack Fuse
  • Developed for U.S. Space Program reliability
  • Available in plug-in or radial lead styles
  • High breaking capacity and military grade options
  • Clear cover option for visual fuse element status

Specifications

Amperage Rating
3 AMPS
Application
electronic equipment & appliances
Brand Name
Littelfuse
Connection Type
Plug-in (short/long leads) or Radial lead
Current Rating
3 A
Material
MICRO™ fuse series
Mounting Type
Plug-in or Radial Lead
Series
MICRO™
Size
Compact H-PACK
Special Features
High breaking capacity
Standard
CSA Approval
Sub Brand
273 Series
Type
Plug In
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9F61 Size B Clips 1.6in

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POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.

LCC5

POWR-JAW clamps improve the contact between fuse and clip. The unnecessary heat from poor contact due to the loss of spring force in the clips can cause nuisance fuse opening and premature aging of surrounding components. High temperature phenolic resin knob designed for the most severe environments 7 sizes to provide effective coverage. Simple design makes installation easy.

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.