Littelfuse LLNRK500 - Littelfuse LLNRK and LLSRK series POWR-PRO™ fuses provide superior overload and short circuit protection for service entrance, main, feeder and general-purpose branch circuits up to 600 amperes. LLNRK/LLSRK series fuses can be installed in existing Class H fuse blocks to upgrade systems containing lower interrupting rating Class H one-time or renewable fuses.
Littelfuse

LLNRK500

Alternate Item Number: LNRK500.X

UPC: 079458330960


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Overview

The **Littelfuse LLNRK500 POWR-PRO™ fuse** from the **LLNRK/LLSRK series** delivers unmatched overload and short-circuit protection for critical electrical systems, including service entrance, main, feeder, and general-purpose branch circuits up to **600 amperes**. Engineered for industrial and commercial applications, these fuses provide a robust solution for upgrading outdated Class H fuse blocks without requiring costly system replacements. The LLNRK500 is designed to seamlessly integrate into existing infrastructure, ensuring compliance with modern safety standards while enhancing operational reliability. **Superior Protection for High-Demand Applications** Electrical systems in industrial, commercial, and utility environments demand reliable protection against overloads and short circuits to prevent equipment damage, downtime, and safety hazards. The **Littelfuse LLNRK500** is specifically engineered to meet these challenges, offering **high interrupting ratings** and **superior thermal performance** compared to conventional Class H fuses. Its advanced design allows it to safely interrupt fault currents, protecting sensitive downstream equipment and ensuring uninterrupted power delivery. **Key Features and Benefits** - **High Interrupting Rating**: The LLNRK500 provides enhanced fault current interruption, reducing the risk of catastrophic failures in high-fault environments. - **Class H Compatibility**: Designed for seamless installation in existing Class H fuse blocks, eliminating the need for costly retrofits or system redesigns. - **Superior Overload Protection**: Engineered to handle sustained overloads while maintaining precise trip characteristics, ensuring long-term reliability. - **Robust Construction**: Built with durable materials to withstand harsh industrial conditions, including vibration, temperature fluctuations, and electrical stress. - **Compliance with Safety Standards**: Meets or exceeds **UL 248** and other industry standards, ensuring full compliance with NEC and OSHA requirements. **Versatile Applications Across Industries** The **LLNRK/LLSRK series** is widely trusted in sectors where electrical reliability is non-negotiable, including: - **Manufacturing Facilities**: Protecting machinery and production lines from electrical faults that could lead to costly downtime. - **Commercial Buildings**: Safeguarding HVAC systems, lighting circuits, and critical infrastructure in offices, hospitals, and data centers. - **Utility and Power Distribution**: Enhancing the safety and reliability of service entrance and feeder circuits in substations and distribution networks. - **Renewable Energy Systems**: Providing protection for solar inverters, wind turbine controllers, and battery storage systems. **Why Choose Littelfuse for Industrial Fuse Protection?** Littelfuse is a global leader in circuit protection, with over **100 years of innovation** in electrical safety solutions. The **POWR-PRO™ series** is a testament to the company’s commitment to delivering high-performance products that meet the evolving needs of modern electrical systems. Professionals across industries rely on Littelfuse fuses for their **proven reliability, extensive testing, and adherence to stringent quality standards**. **Installation and Maintenance Considerations** The **LLNRK500** is designed for easy installation in existing Class H fuse blocks, making it an ideal choice for system upgrades. When selecting a fuse for your application, consider the following: - **Fault Current Rating**: Ensure the fuse’s interrupting rating exceeds the maximum fault current in your system. - **Ambient Conditions**: Verify that the fuse’s operating temperature range aligns with your environment. - **Compliance Requirements**: Confirm that the fuse meets local electrical codes and industry standards. By choosing the **Littelfuse LLNRK500**, you’re investing in a **high-performance, cost-effective solution** that enhances safety, reduces downtime, and ensures long-term reliability for your electrical infrastructure. Trust Littelfuse to deliver the protection your systems deserve.
  • 600A rated for service entrance, main, feeder, and branch circuits
  • Superior overload and short-circuit protection
  • Class H fuse block compatibility for easy upgrades
  • High interrupting rating for enhanced fault current interruption
  • Meets UL 248 and NEC safety standards

Specifications

Amperage Rating
500 Amp
Application
All general purpose circuits
Brand Name
Littelfuse
Current Rating
600 A
Series
LLNRK/LLSRK
Special Features
Time-Delay
Standard
Standard 248-12 UL Listed/CSA
Sub Brand
LLNRK Series
Type
Class RK1
Voltage Rating
600 VAC
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.