Littelfuse KLKR003S - KLKR series Class CC fuses are fast-acting fuses intended for general-purpose branch circuit protection. Their compact size, fast-acting overload response, and their highly current limiting design make them ideal for use in OEM equipment and control panels because Solid-state devices such as SCRs and other electronic equipment generally require fast-acting protection.
Littelfuse

KLKR003S

Alternate Item Number: KLKR003.TS

UPC: 079458189773

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Minimum Qty: 10

Multiplier: 10

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Overview

The **Littelfuse KLKR003S Class CC fast-acting fuse** is a high-performance, compact solution engineered for **general-purpose branch circuit protection** in industrial and electronic systems. Designed to meet the rigorous demands of OEM equipment and control panels, this fuse delivers **rapid overload response** and **superior current-limiting capabilities**, ensuring reliable safeguarding of sensitive electronic components such as SCRs, semiconductors, and other solid-state devices. With its **fast-acting design**, the KLKR003S minimizes downtime and reduces the risk of catastrophic failure in critical applications, making it an indispensable component in modern electrical and electronic protection strategies. Class CC fuses, including the Littelfuse KLKR003S, are widely recognized for their **compact form factor** and **high interrupting rating**, which allows them to safely handle high fault currents without compromising performance. This makes them particularly well-suited for space-constrained environments where efficient power distribution and protection are paramount. The KLKR003S is **UL 248-4** and **CSA certified**, ensuring compliance with North American safety standards and providing peace of mind for engineers and technicians tasked with designing or maintaining industrial control systems. **Key Applications and Industries** The Littelfuse KLKR003S is a versatile solution deployed across a broad spectrum of industries, including: - **Industrial Automation**: Protecting PLCs, motor controllers, and variable frequency drives (VFDs) from transient overloads and short circuits. - **Power Electronics**: Safeguarding inverters, converters, and power supplies in renewable energy systems, UPS units, and battery management systems. - **Control Panels**: Providing branch circuit protection in manufacturing facilities, data centers, and commercial buildings where reliable power distribution is critical. - **Semiconductor Manufacturing**: Shielding sensitive electronic components in semiconductor fabrication equipment from voltage spikes and current surges. - **Automotive and Aerospace**: Ensuring protection in high-reliability applications such as test equipment, instrumentation, and embedded systems. **Why Choose Littelfuse KLKR003S?** Littelfuse, a global leader in circuit protection solutions, has built a reputation for innovation and reliability since 1927. The KLKR003S Class CC fuse exemplifies this commitment, offering: - **Fast-Acting Response**: Minimizes damage to downstream components by interrupting fault currents in milliseconds, reducing repair costs and downtime. - **High Current-Limiting Design**: Limits let-through energy to protect sensitive electronics from destructive fault conditions. - **Compact and Space-Efficient**: Fits seamlessly into tight enclosures, optimizing panel design without sacrificing protection. - **Easy Installation and Maintenance**: Compatible with standard Class CC fuse holders and blocks, simplifying retrofits and upgrades in existing systems. - **Proven Performance**: Backed by decades of field experience and rigorous testing, ensuring consistent operation in demanding environments. **Selection and Installation Best Practices** When integrating the Littelfuse KLKR003S into a system, professionals should consider the following: - **Current Rating**: Select a fuse with a rating that matches the load requirements while providing adequate protection against overloads. - **Voltage Rating**: Ensure the fuse’s voltage rating exceeds the system’s operating voltage to prevent arcing or failure. - **Interrupting Rating**: Verify that the fuse’s interrupting rating (typically 200kA for Class CC fuses) exceeds the maximum fault current available at the installation site. - **Environmental Conditions**: Consider ambient temperature, humidity, and vibration to ensure long-term reliability. - **Compliance**: Confirm that the fuse meets relevant industry standards (e.g., UL, CSA, IEC) for the intended application. For engineers and technicians seeking a **trusted, high-performance fuse** for branch circuit protection, the Littelfuse KLKR003S Class CC fuse delivers unmatched reliability, efficiency, and protection. Whether deployed in OEM equipment, control panels, or industrial automation systems, this fuse provides the peace of mind that comes from using a product backed by one of the industry’s most respected names in circuit protection.
  • Fast-acting overload response for rapid fault interruption
  • High current-limiting design protects sensitive electronics
  • Compact Class CC form factor ideal for space-constrained applications
  • UL 248-4 and CSA certified for North American compliance
  • Trusted Littelfuse quality with decades of circuit protection expertise

Specifications

Application
General Purpose
Brand Name
Littelfuse
Current Rating
3 A
Series
KLKR
Series
KLKR Series
Size
Compact
Size
Compact (Class CC)
Special Features
Fast-Acting
Standard
248-4 UL Listed/CSA
Sub Brand
KLKR Series
Type
Class CC
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.