Littelfuse LA50QS12-1 - VERY FAST-ACTI SEMICOND FUSE QS12-1. In response to new equipment requirements, Littelfuse LA50QS series fuses were developed to improve the overall performance of semiconductor fuses. The LA50QS provides the best protection features including lower I2t, longer life when subjected to cyclic loading and lower watts loss. LA50QS is today’s choice for the protection of dynamic solid state equipment. Features: Lowest I2t for greatest protection of semiconductor circuits. Low watts loss for cooler operation. Superior cycling ability gives an equipment design advantage. State-of-the-art protection for 500 volt equipment. Ultra compact sizes allow down-sizing of existing equipment. Applications: Protection of 500 volts or less solid state equipment such as motor drives, UPS, inverters, etc.
Littelfuse

LA50QS12-1

Alternate Item Number: LA50QS121

UPC: 079458055290

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Overview

The Littelfuse LA50QS12-1 is a premier Very Fast-Acting Semiconductor Fuse engineered to deliver unparalleled protection for dynamic solid-state equipment operating at 500 volts or less. Developed in direct response to evolving equipment requirements, the LA50QS series represents a significant advancement in semiconductor fuse technology, offering superior performance characteristics that enhance overall system reliability and longevity. At the core of the LA50QS12-1's exceptional performance is its exceptionally low I²t rating. This critical specification quantifies the total energy a fuse can withstand before rupturing, and a lower I²t value translates directly to more precise and effective protection for sensitive semiconductor components. By minimizing the energy let-through during fault conditions, the LA50QS12-1 drastically reduces the risk of catastrophic damage to expensive power electronics, ensuring greater operational uptime and lower maintenance costs. Beyond its superior fault-clearing capabilities, the LA50QS12-1 is designed for efficiency and endurance. Its low watts loss design contributes to cooler equipment operation, which is crucial for maintaining optimal performance and extending the lifespan of electronic components. Reduced heat generation can also lead to smaller thermal management systems, potentially enabling further equipment miniaturization. Furthermore, the fuse exhibits superior cycling ability, meaning it can withstand repeated current surges and fluctuations without degradation. This resilience is a significant advantage in applications subjected to cyclic loading, such as motor drives and variable frequency drives, where consistent and reliable protection is paramount. The Littelfuse LA50QS12-1 is the definitive choice for safeguarding a wide array of 500V solid-state equipment. Its applications span critical areas of industrial automation and power conversion, including: * **Motor Drives:** Protecting variable speed drives and servo controllers from damaging overcurrents and short circuits. * **Uninterruptible Power Supplies (UPS):** Ensuring the integrity of power conversion stages in critical backup power systems. * **Inverters and Converters:** Safeguarding the semiconductor devices within AC/DC and DC/AC power conversion equipment. * **Power Supplies:** Providing robust protection for high-power industrial power supplies. * **Renewable Energy Systems:** Protecting inverters and power conditioning equipment in solar and wind energy applications. Littelfuse, a globally recognized leader in circuit protection, brings its extensive expertise and commitment to quality to the LA50QS12-1. Professionals trust Littelfuse for its innovative solutions and reliable products that meet stringent industry standards. The ultra-compact size of the LA50QS12-1 is another key benefit, allowing for the down-sizing of existing equipment designs or enabling more compact new product development. This space-saving attribute is increasingly important in today's competitive market where efficiency and footprint are critical considerations. When selecting a fuse for high-performance semiconductor protection, the Littelfuse LA50QS12-1 stands out as a technologically advanced and reliable solution, offering the best in class protection for demanding applications.
  • Lowest I²t rating for maximum semiconductor circuit protection.
  • Low watts loss design ensures cooler operation and extended equipment life.
  • Superior cycling ability withstands repeated load fluctuations.
  • State-of-the-art protection for 500V solid-state equipment.
  • Ultra-compact size enables equipment down-sizing and design flexibility.

Specifications

Amperage Rating
12 A
Application
Protection of Semiconductors
Brand Name
LA50QS Series
Mounting
Ferrule
Series
LA50QS
Size
9/16D 2IN LNG
Size
Ultra compact
Voltage Rating
500 VAC/VDC
Voltage Rating
500 V V
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.