Littelfuse LA30QS70-4 - 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

LA30QS70-4

Alternate Item Number: LA30QS704

UPC: 079458161045

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Overview

The Littelfuse LA30QS70-4 is a high-performance semiconductor protection fuse engineered to provide critical protection for sensitive power semiconductor devices. Designed for applications operating at 300 volts and below, this fuse is an essential component for safeguarding diodes, phase control SCRs, and other heavy-duty power semiconductor elements. Its robust design and advanced features ensure the longevity and reliability of your power electronic systems. At the core of the LA30QS70-4's protective capabilities is its exceptionally low I²t rating. This specification is paramount in minimizing the energy let-through during a short circuit event. By limiting the I²t, the fuse significantly reduces the thermal stress and potential for catastrophic damage to the protected semiconductor components, thereby extending their operational lifespan and preventing costly downtime. This makes it an ideal choice for new applications demanding the highest levels of protection. Furthermore, the LA30QS70-4 incorporates controlled arc voltage technology. During fuse clearing, the generated arc voltage is carefully managed to prevent excessive stress on other circuit components. This controlled clearing process contributes to overall system stability and reduces the risk of secondary failures, a crucial consideration in demanding industrial environments. Littelfuse understands that system integration requires flexibility. The LA30QS70-4 is available with a choice of mounting types, offering versatile options to accommodate unique termination requirements and installation constraints. This adaptability ensures seamless integration into a wide array of equipment designs. For enhanced operational awareness and simplified maintenance, indicator options are also available, allowing for quick and easy identification of a blown fuse, thus streamlining troubleshooting and replacement procedures. With superior DC capabilities, the LA30QS70-4 is particularly well-suited for protecting 300-volt heavy-duty rectifiers and similar high-power DC supplies. These applications often involve significant current surges and fault conditions, where reliable and rapid fuse protection is non-negotiable. The Littelfuse LA30QS series represents a commitment to quality and performance, offering solutions that meet the stringent demands of modern power electronics. Trust Littelfuse, a recognized leader in circuit protection, for your most critical semiconductor protection needs. Key Features and Benefits: * **Low I²t:** Minimizes damage to protected components during short circuits, enhancing device longevity. * **Controlled Arc Voltage:** Reduces stress on circuit components during fuse clearing for improved system reliability. * **Versatile Mounting Options:** Provides flexibility for unique termination requirements and system integration. * **Indicator Options:** Facilitates easy identification of blown fuses for efficient maintenance. * **Superior DC Capabilities:** Ideal for high-power DC applications, including heavy-duty rectifiers. * **300V Semiconductor Protection:** Specifically designed for safeguarding power semiconductor devices at voltages up to 300V. Applications: * Protection of 300-volt heavy-duty rectifiers. * Protection of similar heavy-duty power supplies. * Safeguarding diodes and phase control SCRs. * Protection for other critical power semiconductor devices in industrial and commercial equipment.
  • Designed for protection of Power Semiconductors (Diodes, Phase Control SCRs)
  • Recommended for new applications at 300V and less
  • Low I²t minimizes damage to protected components on short circuit
  • Controlled arc voltage reduces stress to circuit components during fuse clearing
  • Choice of mounting types and indicator options for flexible integration and maintenance

Specifications

Application
Protection of Semiconductors
Brand Name
Littelfuse
Mounting Type
Choice of 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.
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.

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.

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.
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.

LA70QS50-14F

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.

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.