Littelfuse LA100URD73LI1250 - Littelfuse's North American style square body semiconductor fuses provide maximum flexibility in equipment design and ultimate protection for today's power conversion equipment. Available in different body sizes and multiple mounting styles, the broad range of ampere ratings allows great flexibility in equipment design. Engineered to provide state-of-the-art protection for SCR, diodes, thyristors, GTO, and IGBT devices, Littelfuse square body fuses have pure die-cut elements embedded in solidified sand to control arcing and lower l2t. All fuses are also equipped with a blown fuse trip indicator. Features: Choice of mounting styles provides a wide choice for equipment design. Broad range of ampere ratings in a given body size for design flexibility. Very low l2t minimizes damage to protected components. Superior cycling ability for long, reliable life on high cyclic loading. Extremely fast-acting and current limiting for improved protection to equipment. Applications: Protection of rectifiers, inverters, DC drives, UPS systems, reduced voltage motor starters, and other equipment in globally accepted applications.
Littelfuse

LA100URD73LI1250

Alternate Item Number: LA100URD73LI1250

UPC: 079458155471

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Overview

Littelfuse LA100URD73LI1250 North American style square body semiconductor fuses deliver unparalleled protection for today’s high-performance power conversion systems. Engineered with pure die-cut elements embedded in solidified silica sand, these fuses provide superior arc control and minimal l2t values, ensuring critical protection for sensitive semiconductor devices such as SCRs, diodes, thyristors, GTOs, and IGBTs. The LA100URD73LI1250 model, rated at 1250A, is part of Littelfuse’s renowned LA Series, designed to meet the rigorous demands of modern industrial and commercial applications where reliability and precision are non-negotiable. These semiconductor fuses are the preferred choice for engineers and system designers who require fast-acting, current-limiting protection to safeguard power conversion equipment. The square body design offers exceptional mechanical strength and thermal stability, while the multiple mounting styles—including bolt-on, clip-mounted, and DIN rail options—provide the flexibility needed for diverse equipment configurations. Whether deployed in rectifiers, inverters, DC drives, UPS systems, or reduced voltage motor starters, the LA100URD73LI1250 ensures optimal performance under high cyclic loads, thanks to its superior cycling ability and long operational lifespan. Key advantages of the Littelfuse LA100URD73LI1250 include: - **Ultra-fast response time**: Current-limiting design reacts in microseconds to interrupt fault currents, preventing catastrophic damage to downstream components. - **Low l2t values**: Minimizes thermal stress on protected devices, extending their operational life and reducing maintenance costs. - **Blown fuse trip indicator**: Enables quick visual identification of faults, streamlining troubleshooting and reducing downtime in critical applications. - **Broad ampere rating range**: Available in multiple ratings within the same body size, allowing for scalable design flexibility without compromising protection. - **Industry-trusted reliability**: Littelfuse’s reputation for engineering excellence ensures these fuses meet or exceed global standards for semiconductor protection, including UL, IEC, and CSA certifications. Littelfuse’s square body semiconductor fuses are widely adopted across industries such as renewable energy, industrial automation, data centers, and transportation, where power quality and equipment longevity are paramount. Professionals select these fuses for their ability to handle high inrush currents, repetitive cycling, and transient overloads while maintaining precise protection thresholds. Installation is straightforward, with clear labeling and mounting options that integrate seamlessly into existing panels and enclosures. For applications where downtime is costly, the LA100URD73LI1250’s combination of speed, durability, and ease of maintenance makes it an indispensable component in any power protection strategy. Backed by Littelfuse’s decades of expertise in circuit protection, the LA100URD73LI1250 represents the gold standard for semiconductor fuse solutions. Whether protecting high-power inverters in solar farms, DC drives in manufacturing plants, or UPS systems in data centers, this fuse delivers the performance and peace of mind that engineers demand. Trust Littelfuse to safeguard your most critical power conversion equipment with a solution that combines innovation, reliability, and uncompromising protection.
  • 1250A current rating for high-power applications
  • Square body design with multiple mounting styles
  • Ultra-fast current-limiting protection for semiconductors
  • Low l2t minimizes thermal damage to protected devices
  • Blown fuse trip indicator for easy maintenance

Specifications

Application
Protection of Semiconductors
Brand Name
Littelfuse
Current Rating
1250 A
Material
Silica Sand
Mounting Type
Bolt-on, Clip-mounted, DIN rail
Series
LA Series
Special Features
Very-Fast Acting
Standard
UL Recognized
Sub Brand
LA Series
Type
Semiconductor Fuse
Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount

GPM-SRR90

Fuse Block 600VAC 600VDC Class CC 30A 1/4in Quick Connect / Solder 90 angle screw Knob Panel Mount
Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20

E1062696

Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20
Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20

C331156

Fuse Holder UltraSafe™ 800VAC 1000VDC UL Fuse size 14x51 1-Pole Visual Indicator Microswitch Pressure Plate IP20
Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8

1SCM8

Fuse Block 1500VAC 1500VDC 400A 1-Pole Stud M8
9F61 Size B Clips 1.6in

9F61BWW460

9F61 Size B Clips 1.6in
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.