Littelfuse LA30QS400-4TI - 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

LA30QS400-4TI

Alternate Item Number: LA30QS4004TI

UPC: 079458161298


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Overview

The Littelfuse LA30QS400-4TI Semiconductor Protection Fuse (SKU: LA30QS400-4TI) is a high-reliability fuse designed to protect power semiconductor devices such as diodes, phase control SCRs, and other high-power components operating at 300V or below. This fuse is part of the LA30QS series, engineered for critical protection needs in industrial power electronics where component safety and system reliability are paramount. Key specifications include a voltage rating of 300V (AC/DC), a current rating of 400A, and a low I²t rating that minimizes damage to protected components during short-circuit events. The controlled arc voltage feature reduces stress on circuit components during fuse clearing, ensuring predictable and safe operation. The LA30QS400-4TI is available with multiple mounting types to accommodate unique termination requirements, including options for indicator-equipped models to easily identify blown fuses. This fuse series is ideal for protecting heavy-duty rectifiers, power supplies, and other high-current semiconductor applications. With superior DC capabilities and a 200,000 A.I.R. (Amperes Interrupting Rating), the LA30QS400-4TI meets stringent safety and performance standards, including UL recognition for supplementary protection in UL-listed equipment. Its compact design and advanced metallurgical and polymer technologies ensure consistent quality, reliability, and predictable performance in demanding industrial environments. Applications include variable speed drives, UPS systems, DC power supplies, and other power equipment where fast-acting, current-limiting protection is required. The LA30QS400-4TI is manufactured in the USA, adhering to Littelfuse’s rigorous quality and performance standards.
  • 400A current rating for high-power semiconductor protection
  • 300V AC/DC voltage rating for versatile applications
  • Low I²t minimizes damage to protected components during short circuits
  • Controlled arc voltage reduces stress on circuit components during clearing
  • Multiple mounting types and indicator options available
  • 200,000 A.I.R. for reliable interruption of high fault currents
  • UL Recognized for supplementary protection in UL-listed equipment
  • Superior DC capabilities for industrial power electronics
  • Manufactured in the USA with advanced metallurgical and polymer technologies

Specifications

Application
Protection of Semiconductors
Brand Name
Littelfuse
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 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
Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20

E1062696

Fuse Holder Modulostar® Size 10x38 IEC 690VAC 690VDC 3-Pole IP20
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.
9F61 Size B Clips 1.6in

9F61BWW460

9F61 Size B Clips 1.6in

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.