Littelfuse LLSRK600 - RK1 fuses are extremely current-limiting fuses meaning they greatly reduce or eliminate damage to circuits and equipment under short-circuit conditions. Replacing existing Class H, K and RK5 fuses with RK1 fuses is one of the easiest ways to immediately improve the protection of plant workers and equipment.
Littelfuse

LLSRK600

Alternate Item Number: LSRK600.X

UPC: 079458350982

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Overview

The Littelfuse RK1 fuses, identified by SKU LLSRK600, represent a significant advancement in industrial circuit protection. Engineered for extreme current-limiting capabilities, these fuses are designed to drastically reduce or entirely eliminate damage to sensitive circuits and valuable equipment during catastrophic short-circuit events. This superior performance makes them an ideal and immediate upgrade for facilities currently utilizing older Class H, Class K, or RK5 fuse technologies. By transitioning to RK1 fuses, you are proactively enhancing the safety of plant personnel and safeguarding critical operational assets. Littelfuse, a globally recognized leader in circuit protection, leverages decades of expertise to deliver fuses that meet the most demanding industrial requirements. The RK1 series is a testament to this commitment, offering a robust solution for applications where rapid and decisive interruption of fault currents is paramount. Their advanced design ensures exceptionally fast response times, minimizing the duration of fault currents and thereby mitigating thermal and magnetic stresses on electrical systems. This rapid response translates directly into reduced downtime, lower maintenance expenditures, and extended equipment lifespan. Key benefits of integrating Littelfuse RK1 fuses into your electrical infrastructure include: * **Unparalleled Current-Limiting:** Significantly reduces peak let-through current and I²t, minimizing damage. * **Enhanced Safety:** Protects personnel from arc flash hazards and equipment from catastrophic failure. * **Direct Upgrade Path:** Seamlessly replaces existing Class H, K, and RK5 fuses without extensive system modifications. * **Reliable Performance:** Ensures consistent and dependable protection across a wide range of industrial applications. * **Reduced Downtime:** Minimizes operational interruptions by quickly clearing faults. These fuses are indispensable in a variety of high-demand sectors, including: * Industrial machinery and automation * Power distribution systems * Motor control centers * Switchgear and panelboards * Renewable energy installations When selecting fuses for critical industrial applications, professionals prioritize reliability, performance, and compliance with safety standards. Littelfuse RK1 fuses meet these criteria, offering a high degree of protection that is essential for maintaining operational integrity and ensuring a safe working environment. Their ability to provide extreme current limitation is not merely a technical specification; it is a fundamental safeguard that prevents cascading failures and protects investments. The decision to upgrade to RK1 fuses is a strategic one, aimed at bolstering the resilience and safety of any industrial electrical system. The UNSPSC code for this product is 39121627, further categorizing its role in electrical protection systems.
  • Extreme current-limiting capability to minimize damage during short circuits.
  • Direct replacement for Class H, Class K, and RK5 fuses for immediate protection upgrade.
  • Enhances safety for plant workers and protects critical equipment.
  • Designed for rapid fault current interruption, reducing downtime and maintenance.
  • Manufactured by Littelfuse, a trusted leader in circuit protection solutions.

Specifications

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