Littelfuse LA30QS250-4TI - The Littelfuse LA30QS series Semiconductor protection fuses are intended for the protection of Power Semiconductors such as Diodes, Phase Control SCR and other Power Semiconductor devices.  The LA30QS is recommended for new applications providing solutions for your critical protection needs at 300V and less semiconductors. Features: Low l2t minimizes damage to protected components on short circuit. Controlled arc voltage reduces stress to circuit components during fuse clearing. Choice of mounting types provides options for unique termination requirements. Indicator options allow identification of blown fuses. Superior DC capabilities. Applications: Protection of 300 volt heavy duty rectifiers and similar heavy duty power supplies.
Littelfuse

LA30QS250-4TI

Alternate Item Number: LA30QS2504TI

UPC: 079458161274


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Overview

The Littelfuse LA30QS250-4TI is a semiconductor protection fuse engineered for the critical protection of power semiconductor devices, including diodes, phase control SCRs, and other high-power solid-state components operating at 300V and below. This fuse is specifically recommended for new applications requiring robust protection solutions. A key feature of the LA30QS series is its low I²t characteristic, which significantly minimizes damage to protected components during short-circuit events, thereby enhancing system reliability and reducing downtime. Furthermore, the controlled arc voltage design reduces stress on circuit components during the fuse clearing process, a crucial factor for sensitive semiconductor applications. The LA30QS250-4TI offers superior DC capabilities, making it an ideal choice for demanding industrial power supplies. Littelfuse's advanced metallurgical and polymer research, combined with mathematical modeling and statistical analysis, ensures the accuracy, consistent quality, reliability, and predictable performance that defines their semiconductor fuses. This fuse provides reliable interruption of overcurrents up to 200,000 amperes (A.I.R.), meeting current and future system requirements. Its extremely current-limiting nature, with low I²t and peak let-through currents, directly addresses the stringent requirements of semiconductor protection. The LA30QS250-4TI is UL Recognized, signifying its compliance with Underwriters Laboratories' components program and suitability for supplementary protection in UL listed equipment. Low watt losses contribute to cooler operation and reduced power consumption within the circuit. The availability of indicator options allows for quick and easy identification of blown fuses, streamlining maintenance procedures. With a choice of mounting types, the LA30QS250-4TI provides flexibility for unique termination requirements in various equipment designs. This fuse is particularly well-suited for the protection of 300-volt heavy-duty rectifiers and similar heavy-duty power supplies, ensuring the longevity and operational integrity of critical power systems.
  • Protects 300V and less power semiconductors (diodes, SCRs)
  • Low I²t minimizes damage to protected components during short circuits
  • Controlled arc voltage reduces stress on circuit components
  • Superior DC capabilities for heavy-duty applications
  • UL Recognized for reliable supplementary protection

Specifications

Application
Protection of Semiconductors
Brand Name
Littelfuse
Current Rating
250 A
Mounting Type
Various mounting types
Series
LA30QS
Special Features
Very-Fast Acting
Standard
UL Recognized
Sub Brand
LA Series
Type
Semiconductor Fuse
Voltage Rating
300 V
Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series.  They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication.  The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.

LA70QS10-14FI

Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series. They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication. The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.
Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series.  They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication.  The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.

LA70QS40-14F

Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series. They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication. The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.
Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series.  They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication.  The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.

LA70QS20-22FI

Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series. They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication. The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.
The Littelfuse LA60X semiconductor protection fuses are popular for the protection of higher voltage heavy rectifiers such as traction rectifiers.  They can carry long sustained overloads common with heavy-duty apparatus.  The compact hockey-puck; design provides high power protection in a small space. Features: Lowest l2t minimizes damage to protected components on short circuit. Controlled arc voltage reduces stress to circuit components during fuse clearing. Applications: Protection of heavy traction and electrochemical as well as rectifiers and other heavy-duty equipment.

LA60X1200-128

The Littelfuse LA60X semiconductor protection fuses are popular for the protection of higher voltage heavy rectifiers such as traction rectifiers. They can carry long sustained overloads common with heavy-duty apparatus. The compact hockey-puck; design provides high power protection in a small space. Features: Lowest l2t minimizes damage to protected components on short circuit. Controlled arc voltage reduces stress to circuit components during fuse clearing. Applications: Protection of heavy traction and electrochemical as well as rectifiers and other heavy-duty equipment.
Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series.  They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication.  The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.

LA70QS50-14FI

Littelfuse French Cylindrical style semiconductor fuses are an extension to the LA70QS series. They offer a solid-fill design with high interrupting ratings and an optional striker for visual or remote blown fuse indication. The international 14 x 51mm and 22 x 58mm sizes are accepted worldwide.

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.