Littelfuse KLSR010 - KLSR series RK1 fuses were the earliest type of current-limiting fuse developed. Their single-element, silver link design enables them to provide fast-acting overload and short-circuit protection. When used to protect inductive loads such as motors, solenoids, and transformers, KLSR series fuses must be greatly oversized to prevent opening the fuses on harmless inrush currents. In such applications, KLSR series fuses may only provide short-circuit protection. We recommend using POWR-PRO™ LLNRK/LLSRK series RK1, dual-element, time-delay fuses in all new applications requiring the current-limiting ability of UL Class RK1 fuses, or in existing applications where fast-acting RK1 or RK5 fuses have been opening on harmless system surges such as motor starting currents.
Littelfuse

KLSR010

Alternate Item Number: KLSR010.T

UPC: 079458290653

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Minimum Qty: 10

Multiplier: 10

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Overview

The **Littelfuse KLSR010 RK1 fuse** from the **KLSR series** is a high-performance, single-element current-limiting fuse engineered for fast-acting overload and short-circuit protection in demanding industrial environments. Designed with a precision silver link element, this fuse delivers rapid response to fault conditions, ensuring critical equipment and personnel safety while minimizing downtime. As a UL Class RK1-rated fuse, the KLSR010 is ideal for protecting sensitive power distribution systems, transformers, motors, solenoids, and other inductive loads where reliable current interruption is essential. **Key Features and Benefits:** - **Fast-Acting Protection:** The single-element silver link design enables ultra-rapid response to short-circuit faults, reducing the risk of catastrophic equipment damage and electrical fires. This makes the KLSR010 particularly effective in applications where immediate fault isolation is critical. - **Current-Limiting Capability:** Unlike standard fuses, the KLSR010 limits the let-through energy during fault conditions, protecting downstream components from high fault currents. This feature is invaluable in modern industrial systems with high available fault currents. - **Compact and Reliable Design:** Engineered for durability, the KLSR010 is built to withstand harsh industrial conditions, including vibration, temperature fluctuations, and electrical stress. Its robust construction ensures long service life and consistent performance. - **Wide Application Compatibility:** Suitable for protecting power distribution panels, motor control centers, transformers, and other inductive loads. However, due to its fast-acting nature, the KLSR010 may require oversizing when used with motors or solenoids to avoid nuisance tripping during harmless inrush currents. - **Compliance and Trust:** Manufactured by **Littelfuse**, a global leader in circuit protection solutions, the KLSR010 meets rigorous UL and industrial standards, ensuring compliance with safety and performance regulations. **Industry Applications:** The KLSR010 RK1 fuse is widely used in sectors such as manufacturing, oil and gas, mining, utilities, and commercial buildings where reliable power distribution and equipment protection are paramount. Common applications include: - **Motor Protection:** While effective for short-circuit protection, the KLSR010 may need to be oversized for motor circuits to accommodate inrush currents during startup. For applications requiring time-delay protection, Littelfuse recommends its **POWR-PRO™ LLNRK/LLSRK series dual-element fuses**, which provide superior protection against both overloads and short circuits. - **Transformer Protection:** The KLSR010 safeguards transformers from fault currents, preventing damage to windings and core materials. - **Solenoid and Inductive Load Protection:** Ideal for circuits with inductive components, the fuse ensures quick interruption of fault currents while minimizing stress on the system. - **Power Distribution Systems:** Used in panelboards, switchgear, and branch circuit protection to enhance system safety and reliability. **Installation and Selection Considerations:** When selecting the KLSR010 for an application, professionals should evaluate the following: - **Fault Current Rating:** Ensure the fuse’s interrupting rating exceeds the available fault current at the installation point to guarantee safe operation. - **Inrush Current Handling:** For inductive loads like motors, consider oversizing the fuse or opting for a dual-element fuse to prevent nuisance openings during startup. - **Environmental Conditions:** The fuse should be installed in a location that meets its environmental ratings (e.g., temperature, humidity) to ensure optimal performance. - **Compliance:** Verify that the fuse meets local electrical codes and industry standards, such as UL, CSA, or IEC, depending on the region. **Why Choose Littelfuse?** With over a century of innovation in circuit protection, Littelfuse is a trusted name in industrial safety and reliability. The company’s fuses, including the KLSR series, are designed to meet the evolving needs of modern industrial applications, offering unmatched performance, durability, and compliance. Whether for new installations or retrofitting existing systems, Littelfuse provides solutions that enhance operational safety and efficiency. For applications requiring time-delay protection or where fast-acting fuses may nuisance trip, Littelfuse’s **POWR-PRO™ LLNRK/LLSRK series dual-element fuses** are the recommended alternative, offering superior overload and short-circuit protection in a single device. Trust Littelfuse to deliver the right fuse for your industrial protection needs.
  • Fast-acting single-element silver link design for rapid fault response
  • Current-limiting capability reduces let-through energy during faults
  • UL Class RK1-rated for industrial power distribution and motor protection
  • Compact and durable construction for harsh industrial environments
  • Ideal for transformers, solenoids, and other inductive loads

Specifications

Amperage Rating
2 AMP
Application
low amp - space saving
Brand Name
Littelfuse
Material
Silver
Series
KLSR
Special Features
Fast-Acting
Standard
Supplemental Protection
Sub Brand
POWR-GARD BLS Series
Type
UL Supplemental
Package Weight (Imperial)
0.176 L
Package Weight (Metric)
0.080 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.