Littelfuse LRU-663 - Littelfuse® fuse reducers allow smaller size fuses to be installed into existing fuse clips to prevent overfusing.
Littelfuse

LRU-663

Alternate Item Number: LRU663

UPC: 079458938920

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Overview

The Littelfuse LRU-663 fuse reducer is an essential component for industrial and commercial electrical systems requiring precise circuit protection. This innovative device is engineered to facilitate the installation of smaller amperage fuses into existing fuse clips designed for larger fuse sizes. This capability is crucial for preventing overfusing, a common issue that can lead to equipment damage, fire hazards, and costly downtime. By allowing for the correct fuse rating to be installed, the LRU-663 ensures that circuits are protected according to their specific load requirements, maintaining system integrity and safety. Designed with durability and reliability in mind, the Littelfuse LRU-663 is constructed from high-quality materials to withstand demanding industrial environments. Its precise engineering guarantees a secure fit within standard fuse clips, eliminating concerns about loose connections or intermittent faults. This product is particularly valuable during equipment upgrades or maintenance when replacing an entire fuse block or rewiring is not feasible or cost-effective. The LRU-663 offers a practical and economical solution to maintain optimal circuit protection standards. Key benefits and applications of the Littelfuse LRU-663 include: * **Prevents Overfusing:** Ensures that only the appropriate fuse rating is used, safeguarding sensitive equipment from excessive current. * **Cost-Effective Upgrades:** Allows for the use of smaller, more appropriately rated fuses without the expense of replacing existing fuse holders. * **Enhanced Safety:** Contributes to a safer electrical environment by adhering to correct circuit protection principles. * **Versatile Application:** Suitable for a wide range of industrial, commercial, and even automotive applications where fuse size compatibility is a concern. * **Durable Construction:** Built to last in harsh conditions, providing long-term reliable performance. Littelfuse is a globally recognized leader in circuit protection technology, renowned for its commitment to quality, innovation, and safety. Their extensive product portfolio, including fuse reducers like the LRU-663, is trusted by professionals worldwide. When selecting a fuse reducer, professionals prioritize products that offer a secure connection, correct electrical conductivity, and long-term durability. The LRU-663 from Littelfuse meets these critical requirements, making it a dependable choice for maintaining and upgrading electrical protection systems. This product exemplifies Littelfuse's dedication to providing solutions that enhance the safety and efficiency of electrical installations across various sectors.
  • Facilitates installation of smaller fuses into larger fuse clips.
  • Prevents overfusing, protecting equipment and preventing hazards.
  • Cost-effective solution for circuit protection upgrades.
  • Durable construction for reliable industrial use.
  • Ensures proper circuit protection and system safety.

Specifications

Application
Industrial
Brand Name
Littelfuse
Material
High-quality materials
Series
LRU
Special Features
Simple Installation
Standard
UL Listed CSA Certified
Sub Brand
LRUR Series
Type
Fuse Reducer

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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.