Littelfuse LLNRK020 - 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

LLNRK020

Alternate Item Number: LNRK020.T

UPC: 079458330717

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Overview

The Littelfuse LLNRK020 POWR-PRO™ fuse, part of the robust LLNRK/LLSRK series, is engineered to deliver exceptional overload and short-circuit protection across a wide spectrum of critical electrical applications. This high-amperage fuse is specifically designed for service entrance, main distribution panels, feeder circuits, and general-purpose branch circuits, reliably safeguarding systems operating at up to 600 amperes. Its primary function is to prevent catastrophic damage to electrical equipment and wiring by swiftly interrupting fault currents, thereby enhancing operational safety and minimizing downtime in demanding industrial and commercial environments. A significant advantage of the LLNRK020 is its compatibility with existing Class H fuse blocks. This feature allows for a straightforward and cost-effective upgrade path for facilities currently utilizing lower interrupting rating Class H one-time or renewable fuses. Instead of undertaking a complete overhaul of the fuse block infrastructure, users can simply replace older, less capable fuses with the advanced LLNRK020, instantly boosting the protection level and ensuring compliance with contemporary electrical safety standards. This upgrade capability is invaluable for maintaining the integrity and reliability of aging electrical systems while incorporating modern protection technologies. The Littelfuse POWR-PRO™ LLNRK020 fuse is built to withstand the rigors of industrial settings, offering a dependable solution for protecting sensitive machinery and ensuring continuous power flow. Its robust construction is a testament to Littelfuse's commitment to quality and performance in the protection device market. Key benefits include: * **Superior Protection:** Offers advanced overload and short-circuit protection up to 600A. * **Seamless Upgrades:** Designed for direct installation into existing Class H fuse blocks, facilitating system modernization. * **Enhanced Safety:** Minimizes risk of electrical fires and equipment damage due to faults. * **Reliable Performance:** Engineered for consistent operation in demanding industrial and commercial applications. * **Cost-Effective Solution:** Avoids the expense of replacing entire fuse block assemblies. Industries such as manufacturing, data centers, utilities, and large commercial buildings will find the LLNRK020 to be an indispensable component in their electrical protection strategy. By choosing Littelfuse, a globally recognized leader in circuit protection, customers benefit from decades of expertise and a reputation for producing high-quality, reliable components. The LLNRK020 fuse represents a smart investment in the longevity and safety of any electrical distribution system requiring robust, high-amperage protection.
  • Littelfuse LLNRK020 POWR-PRO™ fuse for superior overload and short-circuit protection.
  • Rated for service entrance, main, feeder, and general-purpose branch circuits up to 600 amperes.
  • Designed for seamless installation in existing Class H fuse blocks, enabling system upgrades.
  • Enhances safety and reliability by protecting against electrical faults and equipment damage.
  • Ideal for industrial and commercial applications requiring robust, high-amperage protection.

Specifications

Amperage Rating
20 AMP
Application
All general purpose circuits
Brand Name
Littelfuse
Special Features
Time-Delay
Standard
Standard 248-12 UL Listed/CSA
Sub Brand
LLNRK Series
Type
Class RK1
Package Weight (Imperial)
0.047 L
Package Weight (Metric)
0.021 kg
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.