Littelfuse LA70Q50-4 - VERY FAST-ACTI SEMICOND FUSE Q50-4. Littelfuse LA70Q semiconductor protection fuses feature a 500 volt AC/DC rating in a compact size (11/2” x 13/32”). LA70Q also has the lowest I2t of all similar fuses and excellent cycling ability. Applications includeinverters and small equipment requiring extremely fast response to faults, without the need to carry sustained heavy overloads. Features: Lowest I2t of any fuse this size for greater protection. Excellent cycling ability gives advantage in equipment design.
Littelfuse

LA70Q50-4

Alternate Item Number: LA70Q504

UPC: 079458153095

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Overview

The Littelfuse LA70Q50-4 is a highly specialized semiconductor protection fuse engineered for critical applications demanding ultra-fast response to electrical faults. Manufactured by Littelfuse, a globally recognized leader in circuit protection, this fuse (SKU: LA70Q50-4) belongs to the LA70Q series and is designed to safeguard sensitive semiconductor devices from damaging overcurrents and short circuits. Featuring a robust 500 Volt AC/DC rating, the LA70Q50-4 is suitable for a wide array of industrial and commercial power systems. Its exceptionally compact form factor, measuring just 1.5" x 0.406", allows for integration into space-constrained designs without compromising protection levels. This makes it an ideal choice for applications such as inverters, variable frequency drives (VFDs), motor control systems, and other power electronic equipment where space is at a premium. A standout feature of the LA70Q50-4 is its exceptionally low I²t rating. The I²t value represents the amount of energy a fuse can withstand before it begins to blow, and a lower I²t indicates a faster and more sensitive response to fault conditions. This superior low I²t capability ensures that the fuse will interrupt the circuit extremely rapidly, minimizing the duration of fault currents and thereby significantly reducing the risk of damage to expensive semiconductor components like IGBTs, MOSFETs, and diodes. This enhanced protection is crucial for maintaining the reliability and longevity of complex power electronic systems. Furthermore, the LA70Q50-4 exhibits excellent cycling ability. This characteristic is vital in applications that experience frequent on/off cycles or transient load changes. Unlike fuses with poor cycling performance, the LA70Q50-4 can withstand these operational stresses without premature degradation or nuisance tripping, contributing to system stability and reducing maintenance requirements. This makes it particularly well-suited for equipment that operates under dynamic load conditions. Key benefits and specifications of the Littelfuse LA70Q50-4 include: * **Ultra-Fast Acting Response:** Designed for immediate interruption of fault currents, protecting sensitive semiconductors. * **Lowest I²t in its Class:** Provides superior protection by minimizing fault energy let-through. * **500V AC/DC Voltage Rating:** Versatile for a broad range of power applications. * **Compact Size (1.5" x 0.406"):** Ideal for space-constrained equipment designs. * **Excellent Cycling Ability:** Withstands frequent operational cycles and transient loads without degradation. * **Reliable Littelfuse Quality:** Backed by the reputation of a trusted leader in circuit protection solutions. When selecting semiconductor protection fuses, engineers prioritize devices that offer the highest level of protection with minimal impact on system performance. The Littelfuse LA70Q50-4 excels in these areas, providing peace of mind and robust defense for critical electronic systems. Its combination of fast-acting interruption, low I²t, excellent cycling capability, and compact size makes it a premier choice for demanding industrial applications where reliability and component protection are paramount.
  • Littelfuse LA70Q50-4 Very Fast-Acting Semiconductor Protection Fuse
  • 500 Volt AC/DC Voltage Rating for versatile application
  • Extremely Low I²t for superior semiconductor protection
  • Compact 1.5" x 0.406" size for space-constrained designs
  • Excellent cycling ability for demanding operational environments

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.